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n l 1/ t. U. . City ca# P�nton Pfan,ninq Divisior, joi.. l D, ht-jz P"—q l ENGINEERING LAND SURVEYING ARCHITECTURE BUILDING SCIENCE LAND USE PLANNING LANDSCAPE ARCHITECTURE INTERIOR DESIGN GRAPHIC DESIGN STRATEGIC MARKETING CONSTRUCTION ADMIN F A- hereby state that this Preliminary Technical Information Report for the Washington State Auto Dealers Association project has been prepared by me or under my supervision and meets the standard of care and expertise which is usual and customary in this community for professional engineers. ALLEN Co T • �y 48491 s GrSTL4$ G SNA L Table of Contents: Section 1 - Project Overview.............................................................3 Section 2 - Conditions and Rquirements Summary ....................................4 Section 3 - Off -Site Analysis..............................................................4 Section 4 - Permanent Flow Control and Water Quality Facility Analysis and Design.......................................................................................8 1. Existing Site Hydrology............................................................8 2. Developed Site Hydrology........................................................8 3. Performance Standards and Goals..............................................9 4. Flow Control System..............................................................9 5. Water Quality System.............................................................9 Section 5 - Conveyance System Analysis and Design ................................ 10 Section b - Special Reports and Studies .............................................. 10 Section 7 - Other Permits............................................................... 10 Section 8 - CSWPPP Analysis and Design .............................................. 1. ESC Plan Analysis and Design .................................................. 2. SWPPS Plan Design............................................................... Section 9 - Bond Quantities, Facility Summaries, Declaration of Covenant..... 1. Bond Quantities Worksheet .................................................... 2. Flow Control and Water Quality Facility Summary Sheet and Sketch.... 3. Declaration of Covenant for Privately Maintained Flow Control and WQ Facilities............................................................................... . 4. Declaration of Covenant for Privately Maintained Flow Control BMPs... Section 10 - Operations and Maintenance Manual .................................. APPFNDICES- Appendix A TIR Worksheet Appendix B Vicinity Map Appendix C Site and Storm Plans Appendix D Soils Map Appendix E Water Quality Calculations Appendix F Conveyance Calculations Appendix G Detention Facility Calculations Appendix H Geotechnical Report and Other Site Studies Appendix J Operation and Maintenance Manual 2 10 10 12 12 12 12 13 13 13 Section 1 - Project Overview The Washington State Auto Dealers Association plans to construct a new administrative building and associated parking lot. The project site lies southeast of the Southwest Grady Way and Raymond Avenue Southwest intersection, in the City of Renton. Approximate area of the project site is 0.77 acres (33,577 square feet). The project will consist of a new administrated building, parking lot, stormwater facilities, utilities, paving of an alleyway on the southern end of the proposed site, and an asphalt overlay of Raymond Ave SW. The alleyway will provide access to parking and emergency vehicle access. The pre -developed site is approximately 0.77 acres, rectangular in shape, fairly flat with a protruding mound of dirt from the adjacent property to the south, and is primarily wooded. The site is bound by Grady Way to the North, Raymond Ave SW to the West, an existing alley to the south, and a one story construction office building to the east. There are no developed structures on site. The developed site will consist of a multi-level conference and administrative building on the western portion of the property. Driveway access will be located on SW Grady Way and the new alley to the south. The proposed access along SW Grady Way would be a minimum of 150' from the SE corner of SW Grady Way and Raymond Ave SW. The site wilL consist of 44 parking stalls (two of which would be ADA accessible), a closed stormwater conveyance system, a basic water quality treatment facility, and a stormwater detention facility. Utilities servicing the site would include gas, power, sanitary sewer, communications, and water for fire, irrigation, and domestic use. There are no manmade conveyance or detention systems on the existing site. The existing soils have low potential for infiltration. Therefore, disposition of stormwater runoff is assumed to either evapotranspirate onsite or sheetfLow offsite into the existing closed conveyance system located along SW Grady Way, Raymond Ave SW, and the alley to the south. Developed disposition of stormwater will consist of a closed conveyance system, a StormFilter manhole, a bioretention swate, and StormTech detention facilities. Stormwater will be detained onsite and leave the site through control structures designed to match the existing 2-, 10-, and 100 -year peaks. 3 Section 2 - Conditions and Requirements Summary Since the project disturbs less than 1 acre of land and proposes disturb over 7,000 square feet of land, per the February 2010 City of Renton Amendments to the King County Surface Water Design Manual, the project would be classified as a "Full Drainage Review." This means that storm water detention and water quality will be required. Section 3 - Off -Site Analysis A Level 1 downstream analysis was performed to provide a qualitative survey of the existing system receiving the project stormwater flow. The stormwater flows to the north to a storm drain manhole at the SW corner of the intersection of SW Grady Way and Raymond Avenue SW then north across SW Grady Way to a manhole located in the King County Vehicle Emissions testing center parking area, approximately 225 feet total. At this point it is believed that the water flows to the west for roughly 650 feet in a closed conveyance system with solid lids across private owned business properties. The water is assumed to enter the storm drain pipe system in the intersection of SW Grady Way and Powell Avenue SW and flow about 200 feet north to SW 10th Street. The stormwater flows west in a closed conveyance system approximately 475 feet through an office building parking lot, where it exits into a deep conveyance ditch. The densely wooded, brush filled conveyance ditch is located on the south side of an extended stay hotel property and is approximately 300 feet long. There is a large concrete culvert, approximately 30" diameter, at the end of the ditch which conveys the storm water to the west under Oakesdale Avenue SW into Springbrook Creek. A combination of a field visit, a study of City of Renton Surface Water Network map and King County Stormwater GIS iMAP were used to track the downstream pathway of the stormwater in excess of 1/a mile. With the exception of the open conveyance ditch located just east of Oakesdale Avenue SW the system is a closed conveyance storm drain mainline with manholes featuring solid lids. Field inspection identified on drainage issue at the concrete culvert located east of Oakesdale Avenue SW. The sidewalk between the culvert opening and Oakesdale Avenue SW has some cracking and sinking/depression. This could be an indication of erosion and/or scouring around the culvert opening. The slope is vegetated but steep from back of sidewalk to culvert. Task 2 also requires a study of the downstream area extending 1 mile from the project site to identify existing drainage or water quality problems. The City of Renton Sensitive Area Maps were studied to identify current issues. The Flood Hazard Areas map shows existing flooding at Springbrook Creek and the conveyance ditch east of the culvert crossing under Oakesdale Ave SW. 4 The WSADA development proposes construction of a complete storm drain facility, including water quality treatment and detention. Stormwater will be treated with a StormFilter manhole, bioretention swale, and detained with a StormTech detention chambers. Detained stormwater will leave the site through control structures designed to match the existing 2-, 10-, and 100 -yr peak flows. Therefore, in conclusion, this project should not create additional or new drainage and water quality problems along its downstream path. 5 WSADA Downstream Analysis Map SW SUNSIET et_vn 117 CT �:...:. kbop ,. qb ti !- % �,- r. .; AW ?"[M ST r `y, iy 39.876 ` o Rent o;n r %+ 10 ii .... Tuk: ila O 42iosrw 19i11.ST. 1CLr9 Casng 0 8 9 8ft COMMENTS. Downstream Analysis Flow Path Tl a irNormation.irxirrded on this rtgp has been oomph np County staff from variety of sources and is subject 10 a xdtl�out nodoe_ KM County makes no represenfahons ar warranses express or implied, as to Acarracy, mplsterxisa, tlmegnesa a �phts to tee use of such information. This document la not intended for use as a wrvey product ICng County shall not he I' fe far any general, special, �ndirest ncidssrtal. or cpnsequarNlal� damages including, but not limited kr, lost revenues or lost profits resu4-q from the u or misuse of the information oor�lned on this map. Ary safe ofLQ this map or ng nty informatlon an this map ig proMited except byvaten permission of Mng qounty. cou Date: 7/1912012 Source: Mng County [MAP - Stormwoter (hitp Iwww.metrokc.gooVrGiSfiMAP) N- FLOOD HAZARD AREAS T �, 1 / Hazard Areas - i+ Y F. .. -� + ally �'�Tx_ 3�•I.L, Yty L�ll rL 1 t fig,/ 14 t}, �� }tJ --- _j � _� r _ ✓�� ��` I l � , � � �, _� I -r • _ rid -�, - tL IL ,s�'',•,Iti \� 4- -Ew '{j',m'f ��.''•-'I� --'���a`_�r. -'T� _ — N-_� ms's �` y!� L, Yl �r � { 4� ���4• l i Lj! �f ,• i r -,'ryi i 1 / l� I I I_ I �.. �,i � !�r,rf_fI 4—�•�T'1' r� r di - t Informalion Technology cis Police Department : Schools Printed or 04282077r•f- I ansa—:U,r Ren�onrG^9Cou ry Fire Stations : LI+ City of Renton This document is a graphic representation, not guaranteed © Valley Medical Center to survey accuracy. and is based on the hest 'information available as of the date shown. This map is inlanded for City display purposes only. 0 D1 as n8 f. ti �3 C__`, I r I I I f f r I M,W Section 4 - Permanent Flow Control and Water Quality Facility Analysis and Design 1. Existing Site Hydrology The existing site is moderately vegetated consisting of scatted b inch to 2 foot diameter cottonwood trees with underbrush growth consisting mostly of blackberries. The area of the site is 0.77 acres. The site slopes from north to south beginning with a 3:1 slope running down off the northern sidewalk becoming generally flat in the middle. There is an existing dirt pile that bisects the southern end of the site diverting stormwater to either side where it either infiltrates, evapot ranspirates, or enters an existing closed conveyance system running under the public alley. 2. Developed Site Hydrology The proposed WSADA site will be divided into 4 sub -basins: the upper and lower parking lot consisting of five catch basins which collect storm water running off the impervious and pervious surfaces routing to the treatment and detention facilities, the northern and western landscaped areas which route stormwater via conveyance swales discharging into a catch basin then discharging into the SC -740 StormTech detention facility, the loading area and public alley which sheet flows water offsite and into an existing conveyance system, and the eastern half of Raymond Avenue SW running along the site, which routes water to a bioretention facility which infiltrates into the SC -310 StormTech Facility. Refer to Appendix C for sub -basin maps for the project site. These sub -basins are analyzed using the King County Runoff Time Series program. Soils: Renton (Re), SCS Hydrologic Soil Group D, Till Rainfall Region: SeaTac Scale Factor: 1.00 The developed site will direct stormwater in directions that closely match the natural directions. 3. Performance Standards and Goals The applicable area -specific flow control facility standard for this project is Peak Rate Flow Control based on the City of Renton Flow Control Applications Map per the City of Renton Amendments to the King County Surface Water Design Manual. There are no modifications to the standard to address onsite or offsite drainage conditions. The flow control requirements will be met using a StormTech detention facility accompanied by an orifice control structure designed to match the 2-, 10-, and 100 -year peaks. The conveyance requirements associated with this project are to convey the 25 -year peak flow with sufficient capacity according to Section 1.2.4.1 of the City of Renton's Amendments to the King County Surface Water Design Manual. Basic treatment BMPs will be applied to all pollution generating surfaces on site. 4. Flow Control System Flow control for the Washington State Auto Dealers Association on-site improvements will be achieved by detaining stormwater on site and releasing at a controlled rate to match existing 2-, 10-, and 100 -year peak flow rates. StormTeche SC-310TM' and SC -740 chambers will be installed under the western frontage sidewalk and southern parking area respectively to provide temporary underground storage for stormwater runoff. The detention facilities where modeled using KCRTS Program as Infiltration Arch Pipe and designed to match the 2-, 10-, and 100 -year predevelopment peak flow rates. Refer to Appendix G for associated calculations and Storm Plan Sheet. Flow control is not required along Raymond Avenue SW because we are not removing the pavement down to sub -grade. Flow control for the new pavement in the new public alley is not practicable due to limited space. Therefore, flow control is being applied along Raymond Avenue to account for the absence of flow control within the alley. The detention facility along Raymond Ave SW will detain 0.11 acres of impervious surface which matches the acreage not being detained within the new public alley. Refer to Appendix G for flow control calculations. 5. Water Quality System All water quality treatment facilities have been designed to treat the required flow rate. There are two treatment facilities associated with this project. A StormFilter Treatment onsite facility and a bioretention swale designed to 0 treat 91% of all influent flows. Refer to Appendix E for associated water treatment facility dimensions and calculations. Section 5 - Conveyance System Analysis and Design 1. Existing Conveyance Systema There is no existing conveyance system located on the site. Runoff that discharges from the project site either sheet flows to Raymond Avenue SW or the partial alley into an existing closed conveyance system. 2. Proposed Conveyance System The proposed stormwater conveyance system will consist of enclosed drainage pipes and drainage swales. Enclosed drainage pipes and swales will be used to convey runoff from the site into a StormTech detention facility. The proposed stormwater conveyance system will be sized to convey runoff from the 25 -year peak event. Refer to Appendix F for conveyance calculations. Section 6 - Special Reports and Studies There have been a total of three geotechnical reports/memos prepared by KLeinfelder, Inc dating from March 10, 2006 to December 9, 2008. A recent geotechnical report using Kleinfelder's finding was received on April 4, 2012 by BRA, Inc. Two Archeological investigations prepared by Historical Research Associates, Inc and Willamette Cultural Resources Associates, Ltd. in February 2008 and November 2008 respectively. These reports and investigations are included in Appendix H. Section 7 - Other Permits The required permits for the Washington State Auto Dealers Association project include, but are not necessarily limited to building, demolition, mechanical, plumbing, and fire alarm. Section 8 - CSWPPP Analysis and Design 1. ESC Plan Analysis and Design The WSADA project implements all applicable ESC measures as described in the City of Renton's Amendments to the King County Surface Water Design Manual. 1. Clearing Limits: Temporary metal fencing will be used to clearly delineate the extents of construction. Areas within the clearing limits HIC will be cleared off all trees and underbrush. Temporary metal fencing and silt fence will be the preferred BMP in order to restrict clearing to approved limits, limit construction to designated construction entrances, and to limit pedestrian access onto the construction site. 2. Cover Measures: The disturbed area is less than 1 acre, is generally flat and has no critical areas or slopes. Temporary cover shall be installed if an area is to remain unworked for more than 7 days during the dry season or for more than 2 consecutive working days during the wet season. The construction schedule plans for work to commence and finish rough grading during the 2012 dry season. Once rough grading and clearing is finished a surcharge of the building foundation is planned for approximately 3 or more months during the wet season. Temporary seeding will be installed in accordance to wet season requirements as described in Appendix D of the King County Surface Water Design Manual. Construction will resume in the spring of 2013 after surcharging of the building pad is complete. Permanent Seeding shall be used in accordance to the Landscape plans associated with the final design package. 3. Perimeter Protection: Perimeter protection from sheetf low offsite shall be accomplished through use of silt fencing. Silt fencing will be installed on the southern end of the site and will be used as primary treatment. Perimeter protection will be used as the sole form of treatment as it has an average slope of 109 or less and a ftowpath of less than 250 feet. The site drains from the north end of the site to the south, has an average slope of 5.6% and a flow path of 110 feet. 4. Traffic Area Stabilization: A stabilized construction entrance wilt be installed as the first step in clearing and grading. Construction road and parking areas will be installed and stabilized immediately after initial grading. Any sediment tracked into the public road will be cleaned. 5. Sediment Retention: The site is small enough to allow perimeter protection through use of silt fencing to act as sediment retention measures on site. Catch basin inlet protection will also be used for catch basins down slope and within 500 feet of the construction area. 6. Surface Water Collection: The site is small enough to allow perimeter protection through use of silt fencing to act as surface water collection measures on site. 7. Dewatering Control: Dewatering activities are not anticipated for this project. However, if during trench excavation operations or foundation installation de -watering is required, the Contractor will pump the water 11 to an approved location on-site to allow sediment to settle out prior to allowing release from the project site. If dewatering occurs from areas where the water has come in contact with new concrete, such as tanks, vaults, or foundations, the pH of the water mist be monitored and must be neutralized prior to discharge onsite or transport offsite in a vacuum flush truck for legal disposal in a manner that does not pollute surface waters. 8. Dust Control: Dust control will be implemented when exposed soils are dry to the point that wind transport is possible. Dust control will be accomplished through use of a sprinkler truck at the discretion of the erosion control specialist onsite. 9. Flow Control: The site is small enough to allow perimeter protection through use of silt fencing to act as flow control measures on site. 2. SWPPS Plan Design Materials include standard construction materials including, but not limited to, CMU blocks, lumber, reinforcing steel, crushed base course, roofing materials, hardware, etc. These materials will be stored on top of a compacted gravel lay down area. Any material with the potential for contamination will be covered with plastic sheeting preventing contact with rain water and will not be allowed to discharge from the site or into the site soils. Waste and Recycling containers will be present onsite and will not allow rainwater to discharge from the containers. The contractor will be responsible for proper groundwater and surface water protection from fuels, oils, and hydraulic fluids. Drip pans will be used as well as secondary containment, if necessary. Vehicle maintenance spill prevention materials shall be on hand at the site prior to the start of any construction activities that require the use of construction machines or vehicles. Section 9 - Bond Quantities, Facility Summaries, Declaration of Covenant 1. Bond Quantities Worksheet A bond quantities worksheet will be provided with the Final Draft of the Technical information Report. 2. Flow Control and Water Quality Facility Summary Sheet and Sketch A flow control and water quality facility summary sheet and sketch will be provided following approval of plans. 12 ■ ■ 3. Declaration of Covenant for Privately Maintained Flow Control and WQ Faci lities A Declaration of Covenant for Privately Maintained Flow Control and WQ Facilities is not included in this preliminary TIR, but will be included in the Final TIR. 4, Declaration of Covenant for Privately Maintained Flow Control BMPs. A Declaration of Covenant for Privately Maintained Flow Control BMPs is not included in this preliminary TIR, but will be included in the Final TIR. Section 10 - Operations and Maintenance Manual An Operations and Maintenance Manual has been prepared for this Preliminary TIR report and can be referenced in Appendix J. 13 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner Phone (206) 433-6300 Address 16000 Christensen Rd. #150 Tukwila, Wa 98188 Project Engineer Steven Sturza Company BORA, Inc. Phone (253) 627-4367 Part3 TYPE OF PERMIT APPLICATION ❑ Landuse Services Subdivison / Short Subd. / UPD Ef Building Services M/F ommerica SFR Clearing and Grading Right -of -Way Use ❑ Other Part 2 PROJECT LOCATION AND DESCRIPTION Project Name Washington State Auto Dealers Associatior DDES Permit # Location Township 23N Range 5E Section 19 Site Address 621 5W Grady Way Renton, Wa 98057 Part 4 OTHER REVIEWS AND PERMITS ❑ DFW HPA ❑ Shoreline ❑ ❑ L3 ❑ COE 404 DOE Dam Safety FEMA Floodplain COE Wetlands Management ❑ Structural RackeryNaultl L3 ESA Section 7 ❑ Other Part 5 PLAN AND REPORT INFORMATION Technical Information Report Site Improvement Plan (Engr. Plans) Type of Drainage Review Full / Targeted / Type (circle one): Full 1 Modified / (circle): rge Site all Site Date (include revision 07.20.2012 Date (include revision 07.20.2012 dates): dates): Date of Final: Date of Final: Part 6 ADJUSTMENT APPROVALS Type (circle one): Standard / Complex / Preapplication / Experimental 1 Blanket Description: (include conditions in TIR Section 2) NIA Date of Approval: 2009 Surface Water Design Manual 1/9/2009 1 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes No Start Date: Completion Date: Describe: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : Commercial Arterial Special District Overlays: Automat! Area A Overlay District Drainage Basin: Duwamish - Green River Stormwater Requirements: Basin Water Quality Treatment and Detention Part 9 ONSITE AND ADJACENT SENSITIVE AREAS ❑ River/Stream ❑ Lake ❑ Wetlands ❑ Closed Depression ❑ Floodplain ❑ Other Part 10 SOILS Soil Type Younger Alluvium ❑ High Groundwater Table (within 5 feet) ❑ Other ❑ Additional Sheets Attached ❑ Steep Slope ❑ Erosion Hazard ❑ Landslide Hazard ❑ Coal Mine Hazard ❑ Seismic Hazard ❑ Habitat Protection Slopes 33%-0% ❑ Sole Source Aquifer ❑ Seeps/Springs Erosion Potential Low 2009 Surface Water Design Manual 1!912009 2 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE ❑ Core 2 — Offsite Analysis ❑ Sensitive/Critical Areas ❑ SEPA ❑ Other ❑ Additional Sheets Attached LIMITATION / SITE CONSTRAINT Part 12 TIR SUMMARY SHEET(provide one TIR Summary Sheet per Threshold Discharge Area Threshold Discharge Area: name or description Washington State Auto Dealers Association (0.77 ac) Core Requirements (all 8 apply) Discharge at Natural Location Number o atural Discharge Locations: 1 Offsite Analysis Level: 0 2 1 3 dated: 07.18.2012 Flow Control Level: QJ 2 / 3 or Exemption Number incl. facility summary sheet Small Site BMPs Conveyance System Spill containment located at: Erosion and Sediment Control ESC Site Supervisor: Jeff Stroud - Mountain Construction Contact Phone: (253) 284-0402 After Hours Phone: 253 284-0402 Maintenance and Operation Responsibility: nva u is If Private, Maintenance L2a Required- Q/ No Financial Guarantees and Provided: Yes ! o Liability Water Quality Type: Basic Sens. Lake / Enhanced Basicm 1 Bog (include facility summary sheet) or Exemption o_ Landsca a Management Plan: Yes 1 No Special Requirements as applicable) Area Specific Drainage Type: CDA 1 SDO 1 MDP / BP 1 LMP / Shared Fac. None Requirements Name: Floodplain/Floodway Delineation Type: Major / Minor 1 Exemption /None 100 -year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: Underground StormTech Detention Facilities Source Control Describe landuse: Commercial (comm./industrial landuse) Describe any structural controls: NIA 2009 Surface Water Design Manual 1/9/2049 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control Nigh -use Site: Yes / Treatment BMP: Maintenance Agreement: Yes !a with whom? Other Drainage Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS Flow Control MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Clearing Limits Water Quality AFTER CONSTRUCTION Stabilize Exposed Surfaces Cover Measures StormTech Remove and Restore Temporary ESC Facilities Perimeter Protection Bioretention Swale StormFilter Clean and Remove All Silt and Debris, Ensure rCG1 Ofd Traffic Area Stabilization Operation of Permanent Facilities Sediment Retention ❑ Flag Limits of SAO and open space Surface Water Collection preservation areas r� Dewatering Control ❑Other rCv Dust Control r00 o� Flow Control Part 14 STORMWATER FACILITY DESCRIPTIONS Note: Include Facility Su mary and Sketch Flow Control Typeffiescription Water Quality Type/Description Detention ❑ Infiltration ❑ Regional Facility ❑ Shared Facility ❑ Flow Control BMPs Ll Other StormTech Ed Biofiltration LJ Wetpool I Media Filtration ❑ Oil Control ❑ Spill Control LlFlow Control BMPs ❑ Other Bioretention Swale StormFilter 2009 Surface Water Design Manual 1/9/2009 4 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTSITRACTS Part 16 STRUCTURAL ANALYSIS Drainage Easement ❑ Cast in Place Vault ❑ Covenant ❑ Retaining Wall ❑ Native Growth Protection Covenant ❑ Rockery a 4' High ❑ Tract ❑ Structural on Steep Slope ❑ Other ❑ Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporp ted into this worksheet and the attached Technical Information Report. To the best of my knowlJoe the inforomatiw wavided here is accurate. 2009 Surface Water Design Manual _ 119!2009 APPENDIX B Vicinity Map 12 WSADA VICINITY MAP I., %Nar,ninglon State Mwc, vp.w't, Eims.,or • 200 tl loom N ovi j& o A An s,v PROJECT LOCATION s\,N & �i-,7on Rpf-ton I El 0 vital chaliges Addiclic-n o s\N 0 Rp.rlon vp., " Lo If) fD :3 S CID s$ F1, te oil Pi ")cjd olw; a APPENDIX C Site and Storm Plans 16 9MG'' OSV-NinS-96lg� OJ700,9619fo 0s = ..i -- - worOUPMWx 31NVN 3 !!j ONIMVhlO ON 1 4 iV'}.S _ 80BPI5652p VON NOISNIHSVM N01 Nig AanuNed M.A -4—A 69EC ���ns 31111 and7 wOsenVl-elid-IIIdlrC 1 tId1Y0H� N:l!Sbt3N .. __ h.3..i_�. 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T Z coo x � �m� ~ w w W o o Ro = s 3 �o�€a� L erF� i w w I € s em FiN?I W _ n M co , a CD LO C. 0 r 0 (/ n 0 n .r f'f1 f 1 f'1 I11 1, /A k ei a CD LO C. 0 r 0 (/ n 0 n .r f'f1 f 1 f'1 I11 1, /A APPENDIX D Soi is Map 14 ..CCU .ZZ4 .SE .E4 ,M ..0 XL .Zu Co 0 m� 41 7' O y N co LL @ N o ❑ 0 (/) n .00 (L) P U c 0 Z p O m F` � W n n v V z W 0 W J a) W L x aD .N a C 0 C CIL ^r, W mm) U U) CL m n a) 0 C O) Em a) U) w� U) 0 ai m a) C U U m3 :� 0-0 CR V 0) 0 n m n CO M c 70 L) E mq L O c E E .Q u] CD mms is n � m = CD Nm + E m O C > L O L � .0 m .. L O w 0 w O O C c c 0 A at -00 CD E a — a a) m O m > CL m E cm E L N p C O ~ O U) C m O m m0 C w O) a) O a) C �C (D E mn 'a 3: Lu E n 0 Em U) UI m a) > :� � m cu as 0 U cm m G 3 ` :3 O o- U) A c u) N > a ,� d lU Il L d O c = CD OCd .c E m cD d QI , :, U y cCL m U m V) O m mts E O w O U L) O It N O (D TCO a) N a) N co N -m L m0 O� Z a O L 2 4- E L)=Q cmc U Cl `N 0 O d}Q�_ `� 4i a7 r a o tZ a C O 0 O w `J 3: E o Cti 0c O Q E!,m (D 0 E w _aN �� n' U 0 a) 0) 110.0 a) D a) �' CD a L EnE m ttscaN Y (n a) c -Q7 L Z E O --. C 0 ca O N Occ L .� c vi N + a A M :) mn c5 m m - in S O O >+ O — O O C m O [fi ., m3 Q (9 .Ca a L L a) 0? .N ? a L� mOi7 C 0 2 � O m1 mU U)a) O n tl) m - m m :CI o E to H — Z inu� o a) E E a U) �.€ o N my7 O O cm m N O ti N 0- U) U) m Z D �6 UI y o- U) A c u) N > a ,� d lU Il L d O c = CD mn mj CL cn L mn p L D d QI , :, U y cCL m U m V) _ 0 xr. m t ;g 2 5 a) o mY my m O •@ m V -m mtl m0 QLL 7 #' 6 `� 1 ' 4 'r��+ me LL t O rL CL and F + p m a am L Q N N Q w rL •Q m1] C '0 p iL O m ,an'- W U o O U > CJ T Q > (La (D o J pO m J m O N c m mm L) m C° a) N 4 CL 0 O tr 4) m m ay` m V) (1) 0 uJ _ N U) c U) pp F5 o n O U) m d N 0 nO c O to d a S ea a mn N my7 O O cm m N O ti N 0- U) U) m Z D �6 Soil Map—King County Area, Washington Map Unit Legend Washington State Auto Dealers Association King County Area, Washington [WA633) Map Unit Symbol Map Unit Name Acres in A01 Percent of AOI Ur Totals for Area of Interest Urban land 1.1 144.4°!a 1.1 100.0% USDA Natural Resources Web Soil Survey 7/1912012 21111111111111 Conservation Service National Cooperative Soil Survey Page 3 of 3 1_1014zIDim Water Quality Calculations 15 D r"I T) A D kl.,� T '` Water Quality Calculations Job Na./Project: 11477 Washington Stale Auto Dealers ASSOClaflon Date: 7/20112 By: KJC Water Quality Calculations: The Washington State Auto Dealers Association project has two proposed stormwater treatment facilities designed to provide the required treatment as determined by the City of Renton's Amendments to the King County water Surface Design Manual. On- site water quality will be provided using a StormFilter manhole and the improvements along Raymond Avenue (in place of the new pavement of the public alley), will be treated via bioretention. The bioretention treatment facility is designed using WWHM3, an approved modeling technique as stated by the City of Renton's Amendments to the King County water Surface Design Manual. Design of the bioretention treatment facility is accomplished by modeling the contributing area flowing into a pond with an infiltration rate of bin/hr and a factor of safety of 4, the total amount infiltrated is the total amount of water receiving treatment as it passes through the bioretention soil mixture. Model inputs and results are shown below. Contributing Basin Input Subbasin Named 1 r: &rlem InhKllow Broundw" Flows To. Tr Pard 7 ITrapewiellail Panel 1 Area in Basin r: - Available Pervious Available Im ei vious l" AA- Forest, Flat J01 (✓ R0.4DS/PL4T r� r r� r ------ r- r-WRAMMM .7] r ,ve, t enn�o..v r ..:EVOM: —] r r� r PROMANUG7., 71 F r r� r r C. PaMua. Mod r POND r� F r� ,Jr PwiousTotal Acres Impervious Total 11 ALM Basin Tatal j j Anes Des!tE! ro select BY: r- 90 X:\Projects\Civ-!\11000\1 1477.A1.00- WA State Auto dealers Association\design\Slcrm\Waler quality treatmenl calculctiors.doc 1/4 Water a B C T� Calculations Job No.JProject: 11477 Washington State Auto Dealers ASSociotic n Date: 7/20/12 Bioretention Modeling Input Name Downstream Connections Facility Type W PMVI*KmAppied to Fack Wo I.., Facility Bottom Elevation (ftj Facility Dimensions Bottom Length (ft) Bottom Width (ft) Effective Depth (It) Left Side Slope (HN) o Bottom Side Slope (HN) o Right Side Slope (HN) 0 Top Side Slope (HN] p Facility Dimension Diagram Ou0e11 1 Outlet 2 Outlet 3 0 1 15 10 IT,ao2ofidal Pond Auto Pond I Quick Pond O Infiltration YES --d Measuied Inl0tration Rate (in/hr] Reduction Factor(infilt^factor) 0.25 ^J Use Wetted Staface Area (sidewalls] {J0 Total Volimelnfibafed(aere-ft) 13.509 Total Volurile Through Risa(acie-ftj 1.218 TotalVdume Through Facility(acie-k) 14.73 Percent Infiltrated 91.73 Oudet Structure Rim Height (h) Q.0 Rises Diametei(inl Fj 8 J Risei Type Flat Notch Type Orifice Diameter Height QMax Number (In) (Ft) (cis) 1 a 2 �- - fp o 3 (a - � Fo--- J o Pond Vokw a at Rind Head (am4t) 002 Pond Increment 0.70 J Show Pond Table Open TaNe =i Use Tide Gate? N0 -H KJC The bioretention area is modeled with b" of ponding and its length and width are modeled to fit inside the landscape strip between Raymond Ave and the proposed sidewalk. The facility is infiltrating 91% of its annual contributing flows which meets the water quality treatment requirement as stated in Section 6. 1.1 Basic Water Quality Menu of the City of Renton's Amendments to the King County Surface Water Design Manual. The pollution generating area from the on-site improvements is treated using a 72" diameter StormFilter Manhole using five treatment cartridges. The treatment facility was sized to 35% of the 2 -year peak flow rate (calculated using KCRTS Program) of the X:\Projects\Civil\11000\I 1477.A1.00- WA State Auto Dealers Association\Design\Stor!n\Water quality treatment caiculations.doc 214 L r" T) t\,j"-V Water Quality Calculations Job No./Project: 11477 Washington State Auto Dealers Association Date: 7120/12 By: KJC contributing pollution generating surfaces being routed to the facility. Model inputs and results are seen below. Storml=ilter Model Inputs �r�1'.MAr'�=�"Y+M!'IV..CV M.V.`%M11Prnilyw.c 'a?•.+Y.i/+fIR�! •and• Area F -Land Use Type -__._... _...._ .. . . ....... ...... _._.._.._... - r Area [acres] Till Forest 10.000 Till Pasture 10.000 Till Grass 10.14 Outwash Forest 10.000 Outwash Pasture 10.0go Outwash Grass 10.000 Wetiand 10.000 Impervious 0.43 Scale Factor 11.000 - Time Step -- - --- --- -- --- -- »._� r Hourly G X15 -minute: --Data Type ___..___.___..__.....___.._..._...____._.._._....___.____._.._�._.__ r Reduced r Historic Compute Total Area If hourly, may disaggregate to 15 -minute V Flow Path Lengths..., Q Longest Path ? Length Slope Land Use Type lftl [V:H] Till Grass 250. 0.01 Impervious 250. 0.01 Return to Land Use ...Men'u............................................................... i ........................................................................................................................................-.............................. .........---........----......---...... Accept Changes or press ESC to Cancel Changes - X:\Projects\Civil\I IOOC\ 1477,A1,00- WA SIato Auio Dealers AssocipYipn\Design\Storm\WaterquoHy treolrnent calcul❑Ylons.doc 3/4 BT) �Ay y1 ts" L Water Quality Calculations Job No./Project: 11477 Washington State Auto Dealers Association Date: 7120112 By: KJC KCRTS Results Flow Frequency Analysis Time Series File.vsadal tsf Project Location Sea -Tao Prob ---Annual Peak Flow Rates --- Flom Rate Rank Time of Peak (CFS) 990 0 431 2 0 225 6 8/27101 18.00 0 162 8 1105z02 15.00 0 431 2 12/08/02 1715 0.196 7 8/26/04 1 00 0 237 S 10/28/04 16:00 0 238 4 10122105 10:00 0.314 3 10/25/06 22:45 0 see 1 1/09/08 6;30 oavuted Peaks 0 536 L -------Flow Frequency Analysis - - Peaks - - Rank Return Prob (CFS) Period 0 598 1 100 00 0 990 0 431 2 25.00 0 960 0.314 3 10 00 0 900 0 239 4 5 00 0 800 n 217 5 3.00 0 667 0.225 6 2 00 0 500 0.196 7 1 30 0 231 0 162 8 1 10 0 091 0 536 50 00 0 980 v Water Quality Flow Rate = 35% * Two year 15 -min peak flow rate QWq= 0.35*0.225 = 0.079 cfs Number of Cartridges Required = Qq * (449/7.5) = 4.7 or 5 Cartridges X:\Projects\Civil\1 1000\11477.A1.00 - WA Sale Auto Deniers Association\Design\S1orm\Wafer quality treatment calculations.doc 4/4 APPENDIX F Conveyance Calculations 16 D rq' T) A D I\JA Flow Cartrol Calculations Job No./Project: 11477 Washington State Auto Dealers Association Date: 7120/12 By: KJC Conveyance Calculations; The WSADA project site will consist of a closed conveyance system with a minimum pipe diameter of 8" and a minimum slope of 0.5%. The calculations below show that the 25 -year peak flow rate for the entire site can be routed through an 8" diameter pipe at a 0.5% slope with sufficient capacity. Q = Flowrate (cfs) n = mannings coefficient d = pipe diameter r = pipe radius A = Cross sectional area of pipe P = Wetted Perimeter R = Hydraulic Radius S = Pipe slope Q25 -yr = 0.587 cfs _Full = (1.49/n)ARv3RS'12 n = 0.013 A = pi*r2 = 0.34 ft2 P = 2*pi*d = 2.09 ft R=A/P=0.157 ft S = 0.005 ft/ft QFult = 0.857 cfs % Full = 0.587/0.857 = 0.685 or 68.5% Full k\'rojects\Civil\ I I OXM 1477.A1.00- WA State Auto Dealers Associciion\Design\Sloan\Conveyance calculofions.doc 111 APPENDIX G Detention Facility Calculations 17 Flow Control Calculations Job No./Project: 11477 Woshl Flow Control Calculations: D k,�� I\JA 5taie Auto Dealers Association Date- 7/20/12 By: KJC The Washington State Auto Dealers Association project has two proposed stormwater detention facilities designed to apply Peak Rate Flow Control Standards as determined by the City of Renton's Amendments to the King County water Surface Design Manual. On-site flow control will be provided using 90 StormTech SC -744 chambers located under the southern parking rows. Off-site flow control along Raymond Avenue (in place of the public alley improvement) will be provided using 27 StormTech SC -310 chambers located underneath a bioretention treatment facility in the planter strip along Raymond Ave SW. The StormTech detention Facility calculations are shown below. The number of chambers needed for the detention facilities is determined based off the Tank Length required to meet Peak Flow Rate Discharge requirements. The number of chambers is determined by dividing the Tank Length by the nominal length of the chambers which is 85.4" or 7.12'. OFF-SITE SC -310 CHAMBERS: Tank Lenth = 190 LF Chamber Length = 7.12 LF # of Chambers = 26.7 or 27 chambers ON-SITE SC -740 CHAMBERS: Tank Lenth = 635 LF Chamber Length = 7.12 LF # of Chambers = 89.2 or 90 chambers Off-site StormTech SC -31 0 Chamber Calculations: Retention/Detention Facility Type of Facility: Tank Rise: Tank Span: Trench Width: Tank Length: Effective Storage Depth: Infiltration Arch Tank 1.33 ft 2.83 ft 4.83 ft 190.00 ft 2.33 ft X:\Projects\Civil\1 ICW\1 1477.A1 .00- WA Slate Aulo Dealers Association\Design\$form\now Control cuicuiations.doc 1/6 D r", T) D t Flow Control Calculations Job No./Project: 11477 Washington State Auto Dealers Association Date: 7/20112 By: KJC Stage 0 Elevation: 0.00 ft Storage Volume: 1036. cu. ft Riser Head: 2.33 ft Riser Diameter: 18.00 inches Number of orifices: 2 Full Head Pipe Orifice # Height Diameter Discharge Diameter (ft) (in) (CFS) (in) 1 0.00 0.45 0.008 2 1.90 0.33 0.002 4.0 Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage Discharge Percolation (ft) (ft) (cu. ft) (ac -ft) (cfs) (cfs) 0.00 0.00 0. 0.000 0.000 0.00 0.01 0.01 5. 0.000 0.001 0.00 0.02 0.02 10. 0.000 0.001 0.00 0.03 0.03 16. 0.000 0.001 0.00 0.04 0.04 21. 0.000 0.001 0.00 0.14 0.14 73. 0.002 0.002 0.00 0.24 0.24 76. 0.002 0.003 0.00 0.34 0.34 200. 0.005 0.003 0.00 0.44 0.44 265. 0.006 0.004 0.00 0.54 0.54 330. 0.008 0.004 0.00 0.64 0.64 393. 0.009 0.004 0.00 0.74 0.74 455. 0.010 0.005 0.00 0.84 0.84 516. 0.012 0.005 0.00 0.94 0.94 575. 0.013 0.005 0.00 1.04 1.04 629. 0.014 0.006 0.00 1.14 1.14 680_ 0.016 0.006 0.00 1.24 1.24 727. 0.017 0.006 0.00 1.34 1.34 763. 0.018 0.006 0.00 1.44 1.44 791. 0.018 0.007 0.00 1.54 1.54 818. 0.019 0.007 0.00 1.64 1.64 846. 0.019 0.007 0.00 1.74 1.74 874. 0.020 0.007 0.00 1.84 1.84 901. 0.021 0.007 0.00 1.90 1.90 918. 0.021 0.008 0.00 1.91 1.91 920. 0.021 0.008 0.00 1.92 1.92 923. 0.021 0.008 0.00 1.93 1.93 926. 0.021 0.008 0.00 2.03 2.03 953. 0.022 0.009 0.00 2.13 2.13 981. 0.023 0.009 0.00 2.23 2.23 1008. 0.023 0.010 0.00 2.33 2.33 1036. 0.024 0.010 0.00 2.43 2.43 1036. 0.024 0.473 0.00 2.53 2.53 1036. 0.024 1.320 0.00 2.63 2.63 1036. 0.024 2.410 0.00 2.73 2.73 1036. 0.024 3.710 0.00 XAl`rotects\0vil\1 IQW\I 1477.AI.QQ - WA State Auio Dealers Associaiian\Design\Storm\Flow Control calculatiuns.dac M LD r" Yl A D k.J I\,j"V Flow Control Calculations Job No./Project: 114/7 Washing tan State Auto Dealers Association Date: 7120112 By: KJC 2.83 2.83 1036. 0.024 5.180 0.00 2.93 2.93 1036. 0.024 6.600 0.00 3.03 3.03 1036. 0.024 7.130 0.00 3.13 3.13 1036. 0.024 7.620 0.00 3.23 3.23 1036. 0-024 8.090 0.00 3.33 3.33 1036. 0.024 8.520 0.00 3.43 3.43 1036. 0.024 8.940 0.00 3.53 3.53 1036. 0-024 9.340 0.00 3.63 3.63 1036. 0.024 9.720 0.00 3.73 3.73 1036. 0.024 10.080 0.00 3.83 3.83 1036. 0-024 10.440 0.00 3.93 3.93 1036. 0.024 10.780 0.00 4.03 4.03 1036. 0.024 11.110 0.00 4.13 4.13 1036. 0-024 11.430 0-00 4.23 4.23 1036. 0.024 11.750 0.00 4.33 4.33 1036. 0.024 12.050 0.00 Hyd Inflow Outflow Peak Storage Target Calc Stage Elev (Cu -Ft) (Ac -Ft) 1 0.05 0.02 0.01 2.32 2-32 1034. 0.024 2 0.03 ******* 0.02 2.33 2.33 1036. 0.024 3 0.03 0.01 0.01 2.16 2.16 990. 0.023 4 0.03 ******* 0.01 1.87 1.87 910. 0.021 5 0.03 ******* 0.01 1.39 1.39 778. 0.018 6 0.02 0.00 0-01 0.96 0.96 586. 0.013 7 0.03 ******* 0.00 0.59 0.59 362. 0.008 8 0.02 ******* 0.00 0.55 0.55 336. 0.008 ---------------------------------- Route Time Series through Facility Inflow Time Series File:wsadarg_dev-tsf Outflow Time Series File:wsadaRG out Inflow/Outflow Analysis Peak Inflow Discharge: 0.052 CFS at 6:00 on Jan 9 in Year 8 Peak Outflow Discharge: 0.018 CFS at 19:00 on Feb 9 in Year 1 Peak Reservoir Stage: 2.33 Ft Peak Reservoir Elev: 2.33 Ft Peak Reservoir Storage: 1036. Cu -Ft 0.024 Ac -Ft Flow Frequency Analysis Time Series File:wsadarg_out.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- -----Flow Frequency Analysis ------- Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob X:\Frojec1s\Civil\11000\11477.A1.00- WA State AuPo Deolers Association\Design\Storm\Flow Control caiculations.doc 3/6 Br"l T) Av k'.� 1\..-) Flow Control Calculations Job No./Project: 11477 Washington State Auto Dealers Association Date: 7/20/12 On- Site StormTech SC -740 Chamber Calculations: Retention/Detention Facility Type of Facility Tank Rise: Tank Span: Trench width: Tank Length: Effective Storage Depth: Stage 0 Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Infiltration Arch Tank 2.50 ft 4-25 ft 6.25 ft 635.09 ft 4.25 ft 0.00 ft 8783. cu. ft 4.25 ft 18.00 inches 2 KJC X:\Projects\Civil\11000\11477.A1 .00- WA Slate Auto Dealers Association\0esign\5t0rm\Flow Contra) calculahons.doc 4/6 Full Head Pipe Orifice # Height Diameter Discharge Diameter (ft) (in) (CFS) (in) 1 0.00 0.87 0.042 2 2.90 1.01 0.032 4.0 Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage Discharge Percolation (ft) (ft) (cu. ft) (ac -ft) (cfs) (cfs) 0.00 0.00 0. 0.000 0.000 0.00 0.01 0.01 24. 0.001 0.002 0.00 0.02 0.02 49. 0.001 0.003 0.00 0.03 0.03 73. 0.002 0.003 0.00 0.04 0.04 97. 0.002 0.004 0.00 0.05 0.05 121. 0.003 0.005 0.00 0.06 0.06 146. 0.003 0-005 0.00 0.07 0.07 170. 0.004 0.005 0.00 0.17 0.17 413. 0.009 0.008 0.00 0.27 0.27 655. 0.015 0.011 0.00 0.37 0.37 947. 0.022 0.012 0.00 0-47 0.47 1132. 0.026 0.014 0.00 0.57 0.57 1553. 0.036 0.015 0.00 0.67 0.67 1861. 0.043 0.017 0.00 0.77 0.77 2169. 0.050 0.018 0.00 0.87 0.87 2477. 0.057 0.019 0.00 0.97 0.97 2780, 0.064 0.020 0.00 1.07 1.07 3083. 0.071 0.021 0.00 1.17 1.17 3382. 0.078 0.022 0.00 1.27 1.27 3677. 0.084 0.023 0.00 1.37 1.37 3970. 0.091 0.024 0.00 1.47 1.47 4260. 0.098 0.025 0.00 KJC X:\Projects\Civil\11000\11477.A1 .00- WA Slate Auto Dealers Association\0esign\5t0rm\Flow Contra) calculahons.doc 4/6 Flow Control Calculations Job No./Project: D r"' T) A D k..� t\,JA 11477 Washingtor State Auto Dealers Association Date: 7120112 By: KJC 1.57 1.57 4540. 0.104 0.026 0.00 1.67 1.67 4815. 0.111 0.026 0.00 1.77 1.77 5092. 0.117 0.027 0.00 1.87 1.87 5347. 0.123 0.028 0.00 1.97 1.97 5599. 0.129 0.029 0.00 2.07 2.07 5841. 0.134 0.029 0.00 2.17 2.17 6074. 0.139 0.030 0.00 2.27 2.27 6288. 0.144 0.031 0.00 2.37 2.37 6484. 0.149 0.031 0.00 2.47 2.47 6657. 0.153 0.032 0.00 2.57 2.57 6782. 0.156 0.033 0.00 2.67 2.67 6902. 0.156 0.033 0.00 2.77 2.77 7021. 0.161 0.034 0.00 2.87 2.87 7140. 0.164 0.035 0.00 2.90 2.90 7175. 0.165 0.035 0.00 2.91 2.91 7187. 0.165 0.035 0.00 2.92 2.92 7199. 0.165 0.036 0.00 2.93 2.93 7211. 0.166 0.037 0.00 2.94 2.94 7223, 0.166 0.038 0.00 2.95 2.95 7235. 0.166 0.040 0.00 2.96 2.96 7247. 0.166 0.042 0.00 2.97 2.97 7259. 0.167 0.043 0.00 2.96 2.98 7271. 0.167 0.043 0.00 3.08 3.08 7390. 0.170 0.048 0.00 3.18 3.18 7509. 0.172 0.051 0.00 3.28 3.28 7628, 0.175 0.054 0.00 3.38 3.38 7747. 0.178 0.057 0.00 3.48 3.48 7866. 0.181 0.059 0.00 3.58 3.58 7985. 0.183 0.061 0.00 3.68 3.68 8104. 0.186 0.064 0.00 3.78 3.78 8223. 0.189 0.066 0.00 3.88 3.88 8342. 0.192 0.068 0.00 3.98 3.98 8461. 0.194 0.069 0.00 4.08 4.08 8581, 0.197 0.071 0.00 4.18 4.18 8700. 0.200 0.073 0.00 4.25 4.25 8783. 0.202 0.074 0.00 4.35 4.35 8783, 0.202 0.538 0.00 4.45 4.45 8783. 0.202 1.380 0.00 4.55 4.55 8783. 0.202 2.480 0.00 4.65 4.65 8783. 0.202 3.780 0.00 4.75 4.75 8783. 0.202 5.250 0.00 4.85 4.85 8783. 0.202 6.670 0.00 4.95 4.95 8783. 0.202 7.200 0.00 5.05 5.05 8783. 0.202 7.700 0.00 5.15 5.15 8783. 0.202 8.160 0.00 5.25 5.25 8783. 0.202 8.600 0.00 5.35 5.35 8783. 0.202 9.020 0.00 5.45 5.45 8783. 0.202 9.410 0.00 5.55 5.55 8783. 0.202 9.800 0.00 5.65 5.65 8783. 0.202 10.160 0.00 5.75 5.75 8763. 0.202 10-520 0.00 X:\Projects\Civil\1 WOO\I W7.A1 .00- WA State Auto Dealers Association\Design\51cxm\Flow Control calculutions.doc 516 BT) Flow Control Calculations Job No.JProject: 11477 Woshington Siate Auto Dealers Association Date: 7/20/12 By: KJC 5.85 5.85 8783. 0.202 10.860 0.00 5.95 5.95 8783. 0.202 11.190 0.00 6.05 6.05 8783. 0.202 11.520 0-00 6.15 6.15 8783. 0.202 11.830 0.00 6-25 6.25 8783. 0.202 12.140 0.00 Hyd Inflow Outflow Peak Storage Target Calc Stage Elev (Cu -Ft) (Ac -Ft) 1 0.34 0.07 0-07 4.25 4.25 8783. 0.202 2 0.17 ******* 0.07 3.89 3.89 8350. 0.192 3 0.23 0.04 0.04 3.00 3.00 7294. 0.167 4 0.18 ******* 0.03 2.45 2.45 6627. 0.152 5 0.21 ******* 0.03 2.28 2.28 6306. 0.145 6 0.19 0.03 0.03 1.59 1.59 4605. 0.106 7 0.14 ******* 0.02 1.11 1.11 3200. 0.073 8 0.16 ******* 0.02 0.92 0-92 2642. 0.061 ---------------------------------- Route Time Series through Facility Inflow Time Series File:wsada_dev.tsf Outflow Time series File:wsada out Inflow/Outflow Analysis Peak Inflow Discharge: 0.345 CFS at 6:00 on Jan 9 in Year 8 Peak Outflow Discharge: 0.074 CFS at 11:00 on Jan 9 in Year 8 Peak Reservoir Stage: 4.25 Ft Peak Reservoir Elev: 4.25 Ft Peak Reservoir Storage: 8783. Cu -Ft 0.202 Ac -Ft Flow Frequency Analysis Time Series File:wsada out.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates --- Flow Rate Rank Time of Peak (CFS) 0.074 4.25 0.068 2 2/09/01 20:00 0.021 7 12/28/01 17:00 0.031 5 2/28/03 19:00 0.020 8 8/26/04 6:00 0.026 6 1/05/05 15:00 0.032 4 1/18/06 23:00 0.044 3 11/24/06 8:00 0.074 1 1/09/08 11:00 Computed Peaks 0.020 0.92 Flow Frequency Analysis-- - - Peaks - - Rank Return Prob (CFS) (ft) Period 0.074 4.25 1 100.00 0.990 0.068 3.89 2 25.00 0.960 0-044 3.00 3 10.00 0.900 0.032 2-45 4 5.00 0.800 0.031 2.28 5 3.00 0.667 0.026 1.59 6 2.00 0.500 0.021 1.11 7 1.30 0.231 0.020 0.92 8 1.10 0.091 0.072 4.13 50.00 0.980 X:\Projec1s\Civi1\1 1000\11477.A1 .00 - WA State Auto Oec€ers Association\Design\Slorm\Flow Control calculations.doc 616 APPENDIX H Geotechnical Report and Other Site Studies 18 Geotechnical Letter Report New Office Building 621 Southwest Grady Way Renton, Washington Submitted to: Vickie Fabr6 Washington State Auto Dealers Association P.O. Box 58170 Seattle, Washington 98138 Submitted by: MRA, Inc. PO Box 44840 Tacoma, Washington 98448 April 4, 2012 Project No. T12019 TABLE OF CONTENTS 1.0 SITE AND PROJECT DESCRIPTION ........... ....... 2.0 EXPLORATORY METHODS ................................ 3.0 SITE CONDITIONS .............................................. 3.1 Surface Conditions .................................... 3.2 Soil Conditions .......................................... 3.3 Groundwater Conditions ........................... 3.4 Seismic Conditions ................................... 3.5 Liquefaction Potential ................................ 4.0 CONCLUSIONS AND RECOMMENDATIONS .... 4.1 Site Preparation ........................................ 4.2 Spread Footings ........................................ 4.3 Slab on Grade Floors ................................ 4.4 Asphalt Pavement ..................................... 4.5 Structural Fill ............................................. 5.0 RECOMMENDED ADDITIONAL SERVICES....... 6.0 CLOSURE............................................................. List of Tables Page No. ... 1 ........................................................... 1 .......... ............................................... ,....... 2 ................................................................. 2 .......................... .............................. 3 ................................................................. 3 ................................................................. 3 ................................................................. 3 ................................................................. 3 .......................................... ...— ...... ........... 4 ...................................... I..... 5 ................................................................ 7 .......................................................... 7 ..... ....................... ................................ 8 ........................................................ 9 ............... ..... ...... .......................... I.......... 10 Table 1. Approximate Locations, Elevations and Depths of Explorations....................................................2 List of figures Figure 1 _ Topographic and Location Map Figure 2. Site and Exploration Plan APPENDIX A Logs of Kleinfelder Explorations and Laboratory Test Results PO Box 44840 Tacoma, WA 98448 253-537-9400 253-537-9401 Fax E3RA April 4, 2012 T12019 Washington State Auto Dealers Association P.O. Box 58170 Seattle, Washington 98138 Attn: Vicki Fabr6 Subject: Geotechnical Letter Report New Office Building 621 Southwest Grady Way Renton, Washington Dear Ms. Fabrd: E3RA is pleased to submit this report providing geotechnical engineering recommendations for the proposed new WSADA Building to be located at 621 Grady Way in Renton, Washington. This report is based on discussions with Mr. Jeff Stroud of Mountain Construction, and our review of logs of subsurface explorations from a previous Geotechnical Engineering Report, dated March 10, 2006, a Preliminary Geotechnical Evaluation, dated January 28, 2008, and a Findings Letter -Limited Soil Characterization, dated December 9, 2008. All of the reviewed documents were provided by Kleinfelder to WSADA. The exploration logs and laboratory test results from the Kleinfelder reports are attached to this report. This report has been prepared for the exclusive use of WSADA, and their consultants, for specific application to this project, in accordance with generally accepted geotechnical engineering practice. 1.4 SITE AND PROJECT DESCRIPTION The site is a trapezoidal parcel that measures approximately 343 feet east to west and 100 feet north to south. It is located at the southeast intersection of SW Grady Way and Raymond Avenue SW in Renton Washington, as shown on the attached Location Map (Figure 1). The site is currently undeveloped and generally slopes down to the south over an elevation change of about 7 feet. Plans call for the construction of a new building with a slab -on -grade floor and a footprint of 6,000 square feet (sf) on the west part of the site with associated parking on -grade parking on the east part of the site. Building options include a 3,000 sf second story with no elevator or a 5,000 sf second story with an elevator. Floor grade of the new building has yet to be determined. 2.0 EXPLORATORY METHODS Kleinfelder conducted six test pit explorations at the site on at the project site on January 11, 2006 and two geotechnical auger borings on the site on February 7, 2006. E3RA observed the site on March 15, 2012. The exploration program used in our analysis included: April 4, 2012 T12019 / WSADA Renton Office Building Report E3RA, Inc. Review of the six test pit logs (TP -1 througb TP -6) and two boring logs (B-1 and B-2), used in the March 10, 2006 and January 29, 2008 Kleinfelder reports; Review of two sieve analyses and two Atterberg Tests conducted for the Kleinfelder reports; and A review of published geologic and seismologic maps and literature. Table 1 summarizes the approximate functional locations and termination depths of Kleinfelder's subsurface explorations, and Figure 2 depicts their approximate relative locations. TABLE 1 APPROXIMATE LOCATIONS, ELEVATIONS AND DEPTHS OF EXPLORATIONS USED FOR THIS REPORT Termination Depth Exploration Functional Location Elevation (feet) (feet) TP -1 Northeast site 23 13 TP -2 North -central site 23 15 TP -3 Northwest site 23 14 TP -4 Southeast site 22 13 TP -5 South-central site 23 11 TP -6 Southwest site 23 12 B-1 Southeast site 23 44 B-2 Northwest site 1 21 44 Elevation information: From Kleinfelder logs It should be realized that the explorations performed and utilized for this evaluation reveal subsurface conditions only at discrete locations across the project site and that actual conditions in other areas could vary. Furthermore, the nature and extent of any such variations would not become evident until additional explorations are performed or until construction activities have begun. If significant variations are observed at that time, we may need to modify our conclusions and recommendations contained in this report to reflect the actual site conditions. 3.0 SITE CONDITIONS The following sections present our observations, measurements, findings, and interpretations regarding, surface, soil, groundwater, seismic, and liquefaction conditions. 3.1 Surface Conditions The site is 4 to 5 feet lower than the right of way of SW Grady Way, which forms the north site boundary. The remainder of the site is relatively level, except at the central part of the south boundary, where the edge of an offsite soil stock pile overlaps the boundary line and grades rise a few feet, and the west part of the south boundary area, where grades descend a foot or two. Vegetation on the day of our site visit (March 15, 2012), consisted of scattered, i to 2 foot diameter cottonwood trees with under brush growth comprised mostly of blackberries. No ponds streams or other surface hydrologic features were observed. No seeps, springs or other surface expressions of groundwater were observed. A graveled turnout extends onto the site from Raymond Avenue SW on the west boundary. April 4, 2012 ORA, Inc. Ti 20191 WSADA Renton Office Building Report 3.2 Soil Conditions The exploration logs indicate that the site is overlain by 3 to 6 inches of topsoil. On the north park of the site, south of SW Grady Way, 4 to 5 feet of fill, consisting of medium dense to dense silty sand with varying amounts of gravel, organics, and construction debris, was encountered. The fill thinned to foot in thickness, or completely disappeared, on the south part of the site. Near the surface on the south part of the site, and underlying the fill, at depths of 4 to 5 feet on the north part of the site, alluvium, comprised of soft to medium stiff silt and loose, silty fine sand, was encountered. This alluvial layer extended down to a depth of 13'/Z feet below existing grades on the cast part of the site and 24 feet below existing grades on the west part of the site. Underlying the sofVloose alluvial layer, a second alluvial layer, comprised of medium dense to very dense sand with gravel was encountered in the two auger borings. The exploration logs and laboratory soil tests in the attached Kleinfelder reports (Appendix A) provide a detailed description of the soil strata encountered in the subsurface explorations used for our report. 3.3 Groundwater Conditions Groundwater was observed at depth ranging from 6 to 9 feet below existing grades during the times of exploration (January 11, 2006 and February 7, 2006). Because the explorations were conducted during the middle of the wet season, these levels likely approximate the seasonal high groundwater level; groundwater levels would likely be lower during the summer and early fall. 3.4 Seismic Conditions Based on our analysis of subsurface exploration logs and our review of published geologic maps, we interpret the onsite soil conditions to correspond with site class D, as defined by Table 1613.5.2 of the 2009 International Building Code (IBC). 3.5 Liquefaction Potential Liquefaction is a sudden increase in pore water pressure and a sudden loss of soil shear strength caused by shear strains, as could result from an earthquake. Research has shown that saturated, loose sands with a fines (silt and clay) content less than about 20 percent are most susceptible to liquefaction. Based on the grain size analyses, the upper, soft/loose alluvium is too silty to easily liquefy and the deeper, more granular alluvium is too well consolidated to liquefy. 4.0 CONCLUSIONS AND RECOMMENDATIONS Plans call for the construction of a one or two story building that might include an elevator. R is unknown if grades will be raised. We offer these conclusions and recommendations: • Foundation ions: Over -excavation of spread footing subgrades and construction of structural fill bearing pads will be necessary for foundation support of the building. If foundation construction occurs during wet conditions, it is likely that a geotextile fabric, placed between bearing pads and in situ soils, will also be necessary. If fill is to be placed to raise grades, we recommend that the bearing pads be constructed before fill placement. Recommendations for Spread Footings are provided in Section 4. • Floor Options: Floor slab sections should be supported on a subbase of structural fill at least 2 feet thick. If floor construction occurs during wet conditions, it is likely that a geotextile 3 April 4, 2012 T12019 / WSADA Renton Office Building Report PRA, Inc. fabric, placed between subbase and in situ soils, will also be necessary. Recommendations for Slab -on -Grade Floors are provided in Section 4. • Elevator Support: Because it is possible that an elevator would need pile support, we recommend that E3 RA be notified to provide elevator support recommendations if an elevator is part of development plans. • Filling to Raise Grade: We recommend that fill placed to raise grade consist of compacted structural fill that confirms to structural fill described in Section 4. To pre -induce settlement, we recommend that any fill placed to raise grades be left in place for a minimum of 3 months. If fill placement occurs during wet conditions, it is likely that a geotextile fabric, placed between under the placed fill and in situ soils, will be necessary. Asphalt Pavement: We recommend that at a subbase at least 2 feet thick of compacted structural fill be used to support asphalt pavement sections onsite. Properly compacted structural fill used to raise grades can be used for pavement subbase. If construction occurs during wet conditions, it is likely that a geotextile fabric, placed between subbase fill and in situ soils, will also be necessary. Pavement recommendations are provided in Section 4. The following sections of this report present our specific geotechnical conclusions and recommendations concerning site preparation, spread footings, slab -on -grade floors, pin piles, drainage systems, and structural fill. The Washington State Department of Transportation (WSDOT) Standard Specifications and Standard Plans cited herein refer to WSDOT publications M41-10, .Standard Specifications for Road, Bridge, and Municipal Construction, and M21-01, Standard Plans for Road, Bridge, and Municipal Construction, respectively. 4.1 Site Preparation Preparation of the project site should involve erosion control, temporary drainage, clearing, stripping, cutting, filling, excavations, construction equipment access, and subgrade compaction. Erosion Control: Before new construction begins, an appropriate erosion control system should be installed. This system should collect and filter all surface water runoff through silt fencing. We anticipate a system of berms and drainage ditches around construction areas will provide an adequate collection system. Silt fencing fabric should meet the requirements of WSDOT Standard Specification 9-33.2 Table 3. In addition, silt fencing should embed a minimum of 6 inches below existing grade. An erosion control system requires occasional observation and maintenance. Specifically, holes in the filter and areas where the filter has shifted above ground surface should be replaced or repaired as soon as they are identified. TemporM Drainae: We recommend intercepting and diverting any potential sources of surface or near -surface water within the construction zones before stripping begins. Because the selection of an appropriate drainage system will depend on the water quantity, season, weather conditions, construction sequence, and contractor's methods, final decisions regarding drainage systems are best made in the field at the time of construction. Clearing and Stripping: The construction areas should be cleared and stripped of all organic soils after surface and near -surface water sources have been controlled. The explorations used for this report indicate that 3 to 6 inches of topsoil overlies the site. 4 April 4, 2012 E3RA, Inc. T12019 / WSADA Renton Office Building Report Site Excavations: Based on our review of site explorations, we expect that excavations will medium dense fill and soft/loose in situ soils. No special equipment will be necessary to rapidly excavate site soils. Dewatering: Explorations indicate that groundwater can generally be found within 6 to 9 of the surface during the wet season. We anticipate that an internal system of ditches, sumpholes, and pumps will be adequate to temporarily dewater excavations down to depths of 6 feet during the wet season, but excavations deeper than 6 feet will likely require expensive dewatering equipment, such as well points. These depths can likely be extended a foot or two during the dry season. Site Excavations: Based on our review of site explorations, we expect that excavations will medium dense fill and soft/loose in situ soils. No special equipment will be necessary to rapidly excavate site soils. Construction Equipment Access: Because native soils at or near the surfaced of the site are comprised mostly of soft silt, a temporary construction access roadway or work pad might be necessary to support heavy construction equipment, during wet conditions. The temporary roadway/ work pad should consist of a layer of quarry spalls placed over an approved geotextile fabric. The need for and thickness of the quarry spall layer will depend on whether and to what extent site grades will be raised. Temporary Cut Slopes: All temporary soil slopes associated with site cutting or excavations should be adequately inclined to prevent sloughing and collapse. Temporary cut slopes in site soils should be no steeper than I %x H:1 V, and should conform to WISHA regulations. Subgrade Compaction: Exposed subgrades for footings and floors should be compacted to a firm; unyielding state before new concrete or fill soils are placed. Any localized zones of looser granular soils observed within a subgrade should be compacted to a density commensurate with the surrounding soils. [n contrast, any organic, soft, or pumping soils observed within a subgrade should be overexcavated and replaced with a suitable structural fill material. Site Filling: Our conclusions regarding the reuse of on-site soils and our comments regarding wet -weather filling are presented subsequently. Regardless of soil type, all fill should be placed and compacted according to our recommendations presented in the Structural Fill section of this report. Specifically, building pad fill soil should be compacted to a uniform density of at least 95 percent (based on ASTM:D-1557). On -Site Soils: We offer the following evaluation of these on-site soils in relation to potential use as structural fill: Topsail: Topsoil and other organic -rich soils are not suitable for reuse as structural fill. Reuse for topsoil should be limited to landscape areas or other nor -structural areas. Fill: The fill that overlies the site contains construction debris and some organic material, so is not reusable as structural fill. If areas of debris and organic -free fill are encountered during the construction process and are thought to be reusable, we recommend that E3RA evaluate their potential for reuse. Alluvial Silt and Silty Sand: The alluvial silt and silty sand that underlies the site is very moisture sensitive and will be impossible to reuse during most weather conditions. April 4, 2012 ORA, inc. T120191 WSADA Renton Office Building Report Permanent Slopes: All permanent cut slopes and fill slopes should be adequately inclined to reduce long-term raveling, sloughing, and erosion. We generally recommend that no permanent slopes be steeper than 2H:1 V. For all soil types, the use of flatter slopes (such as 21H:1 V) would further reduce long-term erosion and facilitate revegetation. Slope Protection: We recommend that a permanent berm, swale, or curb be constructed along the top edge of all permanent slopes to intercept surface flow. Also, a hardy vegetative groundcover should be established as soon as feasible, to further protect the slopes from runoff water erosion. Alternatively, permanent slopes could be armored with quarry spalls or a geosynthetic erosion mat. 4.2 Spread Footings In our opinion, conventional spread footings will provide adequate support for the proposed structure if the subgrades are properly prepared. We offer the following comments and recommendations for purposes of preliminary footing design. Footing Depths and Widths: For frost and erosion protection, the base of all exterior footings should bear at least 24 inches below adjacent outside grades. To limit post -construction settlements, continuous (wall) and isolated (column) footings should be at least 18 and 24 inches wide, respectively. Bearing Subgrades. Structural fill bearing pads, 4 feet thick and compacted to a density of at least 95 percent (based on ASTM:D-1557),should underlie spread footings on this site. If foundation construction occurs during wet conditions, it is possible that a geotextile fabric, placed between the bearing pad and in situ soils, will be necessary. Lateral Overexcavations: Because foundation stresses are transferred outward as well as downward into the bearing soils, all structural fill placed under footings should extend horizontally outward from the edge of each footing a distance equal to the depth of the over -excavation. For instance, an over -excavation of 4 feet should extend 4 feet horizontally from both edges of the footing. Subgrade Observation: All footing subgrades should consist of either firm, unyielding, native soils or suitable structural fill materials. Footings should never be cast atop loose, soft, or frozen soil, slough, debris, existing uncontrolled fill, or surfaces covered by standing water. Bearing Pressures: In our opinion, for static loading, footings that bear on properly prepared, structural fill bearing pads 4 feet thick can be designed for an allowable soil bearing pressure of 2,000 ps£ Footing and Stemwal l Backfill: To provide erosion protection and lateral load resistance, we recommend that all footing excavations be backfilled on both sides of the footings, retaining walls, and stemwalls after the concrete has cured. Lateral Resistance: Footings and stemwalls that have been properly backfilled as recommended will resist lateral movements by means of passive earth pressure and base friction. Footings backfilled with granular structural fill may be designed using a preliminary passive earth pressure of 270 pcf (equivalent fluid weight) and a base friction coefficient of 0.35. A April 4, 2012 E3RA, Inc, T12019 / WSADA Renton Office Building Report 4.3 Slab -On -Grade Floors We offer the following comments and recommendations concerning slab -on -grade floors. Floor Subbase: A structural fill subbase at least 2 feet thick will be needed for floor slabs. All subbase fill should be compacted to a density of at least 95 percent (based on ASTM:D- 1557). . If floor construction occurs during wet conditions, it is likely that a geotextile fabric, placed between the floor subbase and native soils, will be necessary. Capillary Break and Vapor Barrier: To retard the upward wicking of moisture beneath the floor slab, we recommend that a capillary break be placed over the 2 foot thick subbase. This capillary break should consist of a 4 -inch -thick layer of pea gavel or other clean, uniform, well-rounded gravel, such as "Gravel Backfill for Drains" per WSDOT Standard Specification 9-03.12(4), but clean angular gravel can be used if it adequately prevents capillary wicking. In addition, a layer of plastic sheeting (such as Crosstuff, Visqueen, or Moistop) should be placed over the capillary break to serve as a vapor barrier. During subsequent casting of the concrete slab, the contractor should exercise care to avoid puncturing this vapor barrier. Subfloor Drains: We do not recommend the use of subfloor drains for the building Discharge Considerations: If possible, all perimeter drains should discharge to a municipal storm drain; or other suitable location by gravity flow. Check valves should be installed along any drainpipes that discharge to a sewer system, to prevent sewage backflow into the drain system. Runoff Water: Roof -runoff and surface -runoff water should not discharge into the perimeter drain system. Instead, these sources should discharge into separate tightline pipes and be routed away from the building to a storm drain or other appropriate location. Grading and Capping: Final site grades should slope downward away from the building so that runoff water will flow by gravity to suitable collection points, rather than ponding near the building. Ideally, the area surrounding the building would be capped with concrete, asphalt, or low -permeability (silty) soils to minimize or preclude surface -water infiltration. 4.4 Asphalt Pavement Since asphalt pavements will be used for the driveways and parking areas, we offer the following comments and recommendations for preliminary pavement design. Subgrade Preparation: Structural fill subbases appear to be needed under pavement sections. We recommend a minimum subbase fill thickness of 2 feet. Because of the sensitivity of site soils to moisture and disturbance, and depending on site conditions at the time of subgrade preparation, a geotextile fabric, placed between fill and native soils, may be necessary to provide extra support for the pavement. All structural fill should be compacted according to our recommendations given in the Structural Fill section. Specifically, the upper 2 feet of soils underlying pavement section should be compacted to at least 95 percent (based on ASTM D-1557), and all soils below 2 feet should be compacted to at least 90 percent. All soil subgrades should be thoroughly compacted, then proof -rolled with a loaded dump truck or heavy compactor. Any localized zones of yielding subgrade disclosed during this proof -rolling operation should be over excavated to a minimum depth of 12 inches and replaced with a suitable structural fill material. April 4, 2012 E3RA, Inc. T120191 WSADA Renton Office Building Report Pavement Materials: For the base course, we recommend using imported crushed rock. For the subbase course, we recommend using imported, clean, well -graded sand and gravel such as recommended in Section 4.6. Conventional Asphalt Sections: A conventional pavement section typically comprises an asphalt concrete pavement over a crushed rock base course. On a preliminary basis, we recommend using the following conventional pavement sections: Minimum Thickness Pavement Course Parking Areas Driveway Areas Asphalt Concrete Pavement 2 inches 3 inches Crushed Rock Base 4 inches 6 inches Granular Fill Subbase 24 inches 24 inches Compaction and Observation: All subbase and base course material should be compacted to at least 95 percent of the Modified Proctor maximum dry density (ASTM D-1557), and all asphalt concrete should be compacted to at least 92 percent of the Rice value (ASTM D-2041). We recommend that an E3RA representative be retained to observe the compaction of each course before any overlying layer is placed. For the subbase and pavement course, compaction is best observed by means of frequent density testing. For the base course, methodology observations and hand -probing are more appropriate than density testing. 4.5 Structural Fill The term "structural fill" refers to any material placed under foundations, retaining walls, slab -on -grade floors, sidewalks, pavements, and other structures. Our comments, conclusions, and recommendations concerning structural fill are presented in the following paragraphs. Materials: Typical structural fill materials include clean sand, gravel, pea gravel, washed rock, crushed rock, well -graded mixtures of sand and gravel (commonly called "gravel borrow" or "pit -run"), and miscellaneous mixtures of silt, sand, and gravel. Recycled asphalt, concrete, and glass, which are derived from pulverizing the parent materials, are also potentially useful as structural fill in certain applications. Soils used for structural fill should not contain any organic matter or debris or any individual particles greater than about 6 inches in diameter. Because pervious pavement may be planned, import fill should be granular and well draining. Fill Placement: Clean sand, gravel, crushed rock, soil mixtures, and recycled materials should be placed in horizontal lifts not exceeding 8 inches in loose thickness, and each lift should be thoroughly compacted with a mechanical compactor. Compaction Criteria: Using the Modified Proctor test (ASTM:D-1557) as a standard, we recommend that structural fill used for various onsite applications be compacted to the following minimum densities: April 4, 2012 ORA, Inc. T120191 WSADA Renton Office Building Report Sub de Observation and Compaction Testin : Regardless of material or location, all structural fill should be placed over firm, unyielding subgrades prepared in accordance with the Site Preparation section of this report. The condition of all subgrades should be observed by geotechnical personnel before filling or construction begins. Also, fill soil compaction should be verified by means of in-place density tests performed during fill placement so that adequacy of soil compaction efforts may be evaluated as earthwork progresses. Soil Moisture Considerations: The suitability of soils used for structural fill depends primarily on their grain -size distribution and moisture content when they are placed. As the "fines" content (that soil fraction passing the U.S. No. 200 Sieve) increases, soils become more sensitive to small changes in moisture content. Soils containing more than about 5 percent fines (by weight) cannot be consistently compacted to a firm, unyielding condition when the moisture content is more than 2 percentage points above or below optimum. For fill placement during wet -weather site worts, we recommend using "clean" fill, which refers to soils that have a fines content of 5 percent or less (by weight) based on the soil fraction passing the U.S. No. 4 Sieve. 5.0 RECOMMENDED ADDITIONAL SERVICES Because the future performance and integrity of the structural elements will depend largely on proper site preparation, drainage, fill placement, and construction procedures, monitoring and testing by experienced geotechnical personnel should be considered an integral part of the construction process. Consequently, we recommend that E3RA be retained to provide the following post -report services: • Review all construction plans and specifications to verify that our design criteria presented in this report have been properly integrated into the design; • Prepare a letter summarizing all review comments (if required by the City of Renton); • Check all completed subgrades for footings and slab -on -grade floors before concrete is poured, in order to verify their bearing capacity; and • Prepare a post -construction letter summarizing all field observations, inspections, and test results (if required by the City of Renton). E~' Minimum Fill Application Compaction Footing subgrade and bearing pad 95 percent Foundation backfill 90 percent Slab -on -grade floor subgrade and subbase 95 percent Asphalt pavement base 95 percent Asphalt pavement subgrade (upper 2 feet) 95 percent Asphalt pavement subgrade (below 2 feet) 90 percent Sub de Observation and Compaction Testin : Regardless of material or location, all structural fill should be placed over firm, unyielding subgrades prepared in accordance with the Site Preparation section of this report. The condition of all subgrades should be observed by geotechnical personnel before filling or construction begins. Also, fill soil compaction should be verified by means of in-place density tests performed during fill placement so that adequacy of soil compaction efforts may be evaluated as earthwork progresses. Soil Moisture Considerations: The suitability of soils used for structural fill depends primarily on their grain -size distribution and moisture content when they are placed. As the "fines" content (that soil fraction passing the U.S. No. 200 Sieve) increases, soils become more sensitive to small changes in moisture content. Soils containing more than about 5 percent fines (by weight) cannot be consistently compacted to a firm, unyielding condition when the moisture content is more than 2 percentage points above or below optimum. For fill placement during wet -weather site worts, we recommend using "clean" fill, which refers to soils that have a fines content of 5 percent or less (by weight) based on the soil fraction passing the U.S. No. 4 Sieve. 5.0 RECOMMENDED ADDITIONAL SERVICES Because the future performance and integrity of the structural elements will depend largely on proper site preparation, drainage, fill placement, and construction procedures, monitoring and testing by experienced geotechnical personnel should be considered an integral part of the construction process. Consequently, we recommend that E3RA be retained to provide the following post -report services: • Review all construction plans and specifications to verify that our design criteria presented in this report have been properly integrated into the design; • Prepare a letter summarizing all review comments (if required by the City of Renton); • Check all completed subgrades for footings and slab -on -grade floors before concrete is poured, in order to verify their bearing capacity; and • Prepare a post -construction letter summarizing all field observations, inspections, and test results (if required by the City of Renton). E~' April 4, 2012 T120191 WSADA Renton Office Building Report 6.0 CLOSURE E3RA, Inc. The conclusions and recommendations presented in this report are based, in part, on the exploration logs that we analyzed for this report; therefore, if variations in the subgrade conditions are observed at a later time, we may need to modify this report to reflect those changes. Also, because the future performance and integrity of the project elements depend largely on proper initial site preparation, drainage, and construction procedures, monitoring and testing by experienced geotechnical personnel should be considered an integral part of the construction process. E3RA is available to provide geotechnical monitoring of soils throughout construction. We appreciate the opportunity to be of service on this project. If you have any questions regarding this report or any aspects of the project, please feel free to contact our office. Sincerely, E3RA, Inc. Fred E. Rennebaum, L.E.G. Senior Geologist James E. Brigham, P.E_ Principal Engineer FER-.JEB:dj TACOUacoma-scrver�cllOB FMESII2000 JOB FILESIT120I9 WSADA- Renton Office Bidg1T120I9 WSADAREnton Office Building Report.doc Two copies submitted cc: Jeff Stroud Mountain Construction 7457 S Madison St Tacoma, WA 98409 Mark Bergrnan BCRA Architects 2106 Pacific Ave Tacoma, WA 98402 10 0 0 0 m N 0 122'15.000'W 122014.000' W WGS84 122013.000'W T 1 I' lAr APPROXIMATE SITE j y i �� • LOCATION J d 122"15,000' W 122"14,000' W WGS84122013.000' W TN MN 0 1'%tE 17`l° 1 FEET Q SQ7 � 0 RiE1 R$ Map created with TOPO! @ @2003 National Geographic (www,aatianalge09raphic.c000p0) E3RA, Inc. P.O Box 44840 Tacoma, WA 98448 WSADA RENTON OFFICE BUILDING TOPOGRAPHIC AND LOCATION MAP RENTON, WASHINGTON 0 0 0 N 0 FIGURE 11 T12079 W, 1 , 122"15,000' W 122"14,000' W WGS84122013.000' W TN MN 0 1'%tE 17`l° 1 FEET Q SQ7 � 0 RiE1 R$ Map created with TOPO! @ @2003 National Geographic (www,aatianalge09raphic.c000p0) E3RA, Inc. P.O Box 44840 Tacoma, WA 98448 WSADA RENTON OFFICE BUILDING TOPOGRAPHIC AND LOCATION MAP RENTON, WASHINGTON 0 0 0 N 0 FIGURE 11 T12079 C_ Z C) a) c- r m ca O C; ii CV 4= a o O w 2 z LU - c 4 N O L 4 () W CIO cr- LLJ P Q Dr�iaVd bGdan D �.: +, cy TVA 3138ONDO 40iN3W35VW —0� m • 8 - � Q3 �; = = m O bL J m 4 dol W m C) ca F- W r LU U LU LU LLI co r"v [�? r `[ 0- U) ❑ U ❑ a N M u to N Ca x Y N 00 CL� 40 C 0) am ~sir — ¢00 CDS 0 "I" mcr) LL o E � a) M Lo Lo o uj x 0 caLoLo F— N N N +g a W („ o • � a � Z Ll ►� p to 'ONO to Z - z 0QpQ n> 's? V)fr- ��W N CLM mmZp>- I- co Lo W m x c Q Q �{a =QLl- Z:) Z U) < W W LLI rnN(�,7 me 0 Q K x QQ d LLJ o OLLi PWLL. Q C) W rncvth Qozz x z O LLJzd W aoddo zm:2mz Sk knCL ONO - x ��� `' x 00Y r Z a O C3 �D H CV C� d C6 W 0 J � ICD m W Q. ( W LL- .49 L.L9 40 l W z ~ 3„95,5£AON H••� W Z J 0 CD ¢ F" U U J 17 Z OC CD M (Y) W —� "KLEINTILL7ER APPENDIX A FIELD EXPLORATION Soil samples were collected from the borings at 5 -foot intervals using Standard Penetration Test (SPT) sampling techniques (ASTM D1586). The SPT consisted of driving a 1 -318 -inch inside -diameter split spoon sampler a distance of 18 inches into the bottom of the boring. The sampler was driven with a 140 -pound hammer falling 30 inches. The number of blows required to drive the sampler each of three 6 -inch increments was recorded on the boring logs. The number of blows required for the last 12 inches of penetration is called the standard penetration resistance (N -value)- This value is an indicator of the relative density of granular soils or the consistency of fine- grained soils. Soil samples were collected from the test pits at changes in material type. Soil samples collected during the field exploration were classified in accordance with ASTM D2487. All samples were sealed in plastic bags to limit moisture loss, labeled, and returned to our laboratory for further examination and testing. The boring and test pits were monitored by our geologistlengineer who examined and classified the materials encountered, obtained representative soil samples, and recorded pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater occurrence. Upon completion of drilling, the borings were backfilled with a combination of native soil and bentonite chips. Soil classifications were made in the field in accordance with the Unified Soil Classification System, presented on Appendix A-1. Sample classifications and other related information were recorded on the boring and test pit fogs, which are included in this appendix. The stratification lines, shown on the individual logs, represent the approximate boundaries between soil types; actual transitions may be either more gradual or more severe. The conditions depicted are for the date and location indicated only, and it should not necessarily be expected that they are representative of conditions at other locations and times. 64923/SEA5RD59_doc Page i of I March 10, 2046 Copyright 2006 Kleinfelder, Inc_ Proposed Auto Body Shop APPENDIX W Grady Way & Roymond Ave S SOIL CLASSIFICATIQN LEGEND A-1 Renton, Washington KLE{NFELDER Project: 64923 Marcfi 2005 5 TESTING PROGRAM U.S.C.S. I LABORATORY I e u WELLiPIEZO �', ,> �. CONS-rRucTION =cam za Li Surface: forest duff U .� o 5 51LT WITH SAND (ML): gray -brown to brown with red -brown mottling, wet, medium stiff, low plasticity, sortie organics 2 SII observed (rootlets and leaf fiber), 0.0 tsf unconfined compressive strength (pocket 2 penetrometer). 3 - , j ('YOUNGER ALLUVIUM) grades to wet, occasional lenses of sand 15.0 1 SI -2 withsilt. 2 Ali SILT (ML): gray with orange -brown r — 5 mottling, wet, medium stiff to stiff, low to io moderate plasticity, some organics (rootlets), 0.75 to 1.0 tsf unconfined compressive strength (pocket SAI � penetrometer). 1 J YOUNGEP. AULUVIUMJ_ 1 s1-3 SILTY 5TAN17 (SM}: gray, wetW, very I loose, fine- to medium-grained- O_UNG_E_R_AL_L_UVIUM) I i NIL SILS W 7H SAND (ML} gray, wet, very soft, low plasticity, 0.0 tsf unconfined compressive strength (pocket 1 penetromcter)- (YOUNGER ALLUVIUM) I X SI -4 �I _ _--._ ----.- I9 SM i SILTY SANT) (SM]: gray, wei, deme, SI' 1 fine-grained, trace organics (rootlets), trace . 27 lgravel. ! 1 SOLDER ALLUVIUMS _ _ _ J SAND WITH GRi�IVEL (SP)' gray, wet, dense, medium- to coarse, -grained. (OLDER ALLUVIUM) j 35.0 20 SI -5 - grades to very dense, mediuin-grained, 29 X small lenses of silty sand- 25 - 40 SI -6 27 32 3 DATE I)RILLED: 2-7-05 SURFACE ELEVATION (feet): 23.0 DRILLING METHOD, HSA LOGGED BY: F. Reinart TOTAL. DEPTH (feet): 44.0 DRILLER: Subterranen Drilling REVIEWED BY: F. Reinart DIAMETER OF BORING (in):8 inches CASING SIZE: NIA Proposed Auto Body Shop Appendix SW Grady Way & Raymond Ave SW KLEINFELDER Renton, Washington A -Za GEOTEC14NICAL AND ENVIRONMENTAL ENGINEERS BORING LOG SOILS AND MATERIALS TESTING PAGE 1 of 2 U.S.C.S. I SOIL DESCRIPTION Surface: forest duff 51LT WITH SAND (ML): gray -brown to brown with red -brown mottling, wet, medium stiff, low plasticity, sortie organics 2 SII observed (rootlets and leaf fiber), 0.0 tsf unconfined compressive strength (pocket 2 penetrometer). 3 - , j ('YOUNGER ALLUVIUM) grades to wet, occasional lenses of sand 15.0 1 SI -2 withsilt. 2 Ali SILT (ML): gray with orange -brown r — 5 mottling, wet, medium stiff to stiff, low to io moderate plasticity, some organics (rootlets), 0.75 to 1.0 tsf unconfined compressive strength (pocket SAI � penetrometer). 1 J YOUNGEP. AULUVIUMJ_ 1 s1-3 SILTY 5TAN17 (SM}: gray, wetW, very I loose, fine- to medium-grained- O_UNG_E_R_AL_L_UVIUM) I i NIL SILS W 7H SAND (ML} gray, wet, very soft, low plasticity, 0.0 tsf unconfined compressive strength (pocket 1 penetromcter)- (YOUNGER ALLUVIUM) I X SI -4 �I _ _--._ ----.- I9 SM i SILTY SANT) (SM]: gray, wei, deme, SI' 1 fine-grained, trace organics (rootlets), trace . 27 lgravel. ! 1 SOLDER ALLUVIUMS _ _ _ J SAND WITH GRi�IVEL (SP)' gray, wet, dense, medium- to coarse, -grained. (OLDER ALLUVIUM) j 35.0 20 SI -5 - grades to very dense, mediuin-grained, 29 X small lenses of silty sand- 25 - 40 SI -6 27 32 3 DATE I)RILLED: 2-7-05 SURFACE ELEVATION (feet): 23.0 DRILLING METHOD, HSA LOGGED BY: F. Reinart TOTAL. DEPTH (feet): 44.0 DRILLER: Subterranen Drilling REVIEWED BY: F. Reinart DIAMETER OF BORING (in):8 inches CASING SIZE: NIA Proposed Auto Body Shop Appendix SW Grady Way & Raymond Ave SW KLEINFELDER Renton, Washington A -Za GEOTEC14NICAL AND ENVIRONMENTAL ENGINEERS BORING LOG SOILS AND MATERIALS TESTING PAGE 1 of 2 l 17.0 10 1 30.0 20 25 30—�- DATE DRILLED: 2-7.06 a LOGGED BY: F. Reinart 9 IZFVIFWED BY: F. Reinart u.S.C.S. SOIL DESCRIPTION � WI z � Surface: forest duff i TESTING PROGRAM r` SILTY SAND (SM): Might gray -brown LABORATORY FIELD with orange -brown mottling, mo's', dense, fine-grained, occasional construction debris 2 5 [ observed in cuttings. WELLJP[EZ.O > (FILL) r� r CONSTRUCTION � �'� � Z!zw - --- ISILT WITH SAND (ML)�iight� c�' gray -brown with orange to red -orange mottling, moist to wet, medium. stiff, !ow D ¢ Oz of brown peat, trace organics observed 2 S2-2 5 X0 (rootlets), 0.25 to 045 tsf unconfined G compressive strength (pocket 2 U r pcnetrometer). 3 O (YOUNCER ALLUVIUM) 1Grades to wet. _-___ --_-- 4>``f 0 SILTY SAND (SMIJ: gray, wet, Ivry loose, rne-grained, seams of gray sandy I {�7 S2-3 l 17.0 10 1 30.0 20 25 30—�- DATE DRILLED: 2-7.06 a LOGGED BY: F. Reinart 9 IZFVIFWED BY: F. Reinart u.S.C.S. SOIL DESCRIPTION � WI z � Surface: forest duff S S2-6 - grades to dense, coarse-grained, no 14 observable silt in sampler. 19 { SURFACE ELEVATION (feet): 21.0 DRILLING METHOD: HSA TOTAL DEPT14 (feet): 44.0 DRILLER: Subterranen Drilling DIAMETER OF BORING (to): $ inches CASING SIZE: N/A Proposed Auto Body Shop SW Grady Way & Raymond Ave SW MIJKLEINFELDER Renton, Washington GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS $ORTNG LOG SOILS AND MATERIALS TESTING FELT NUMBER: 64923 B-2 Appendix A -3a PAGE 1 of 2 SN1 r` SILTY SAND (SM): Might gray -brown II with orange -brown mottling, mo's', dense, fine-grained, occasional construction debris 2 5 [ observed in cuttings. (FILL) 34 19 ML - --- ISILT WITH SAND (ML)�iight� gray -brown with orange to red -orange mottling, moist to wet, medium. stiff, !ow plasticity, thin (118 to I/4 inch thick) seam of brown peat, trace organics observed 2 S2-2 (rootlets), 0.25 to 045 tsf unconfined compressive strength (pocket 2 pcnetrometer). 3 (YOUNCER ALLUVIUM) 1Grades to wet. _-___ --_-- 4>``f SILTY SAND (SMIJ: gray, wet, Ivry loose, rne-grained, seams of gray sandy I {�7 S2-3 silt. (YOUNGER ALLUVIUM) 1 1, ] CCC 2 /� 52 4-- SM ' SILTY SAND (5?�4): gray, eget, loose, I }` fine-grained, Trace organics (rootlets). 2 (YOUNGBR A i.L,UViUM) 2 52-5 6 SP SAND WITH GRAVEL. (SF): gray to black, wet, medium dense; medium- to coarse-grained, trace Silt. (OLDER ALLIfVl_ ANI) S S2-6 - grades to dense, coarse-grained, no 14 observable silt in sampler. 19 { SURFACE ELEVATION (feet): 21.0 DRILLING METHOD: HSA TOTAL DEPT14 (feet): 44.0 DRILLER: Subterranen Drilling DIAMETER OF BORING (to): $ inches CASING SIZE: N/A Proposed Auto Body Shop SW Grady Way & Raymond Ave SW MIJKLEINFELDER Renton, Washington GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS $ORTNG LOG SOILS AND MATERIALS TESTING FELT NUMBER: 64923 B-2 Appendix A -3a PAGE 1 of 2 z C F a c. R u. v, E- F a L z 4 :` L SM 13 SOIL DESCRIPTION Surface- forest duff Topsoil (ineh s thick). _ _ _ _ _ - _ - - - SILT Y SAND WITH GRAVEL (SNI): -ray-brow wet, mediu.n dense, fine -Brined, occasion31 cobhies to 9 inches ir. ;ongest dimension. (F1Li.) - grades to moist. -' ^ SILT WITH SAND (ML): gray with red -brown mottling, moist, mc&rr. stiff, low plass, city, trace organics observed (rootlets). (YOUNGER ALLUVIUM) grades to v.let - 1orades to gray, sa.TY SAND (SNI): gray, wet, toose, fine-grai.ne2 (YOUNGER ALLUVIUTA) Test pit was completed to a depth of 13 feet below ground surface. Groundwater was cneauntered ❑t a depth oC6 feet below ground surface during excavat'an Tcst pit was backfilled with excavated soil and tamped with backhoc shovel. Q DATE EXCAVATED' :il 1;2006 APPROYI1v7ATE ELEVATION: 21 M iLEVIi-'WFD BY:f. Reirart c + SAMPLE TYPE: � Bulk T Gr ah f� '5h' -.'6Y; »t,e a STP1-I STF1-2 20 LOGGFD BY: F. R--inat, EQUlNVFN`f: Backhoe OTHER TESTS+ *TESTS: WMo-slureCanrent(16f, D-Dn,Oer��i11'fP�ii, T1:=To:va;32, PD-PocketPeriet-omerer, G=Gram Sine, KT�EINFELDER Proposed Auto Body Shop SW Grady Way & Raymond Ave SW GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS Renton, Washington SOILS AND MATERIALS TESTING PROJECT N0.64923 TEST PIT LOG TP -1 Appendix A-4 �z 0 I �U Topsoil (ineh s thick). _ _ _ _ _ - _ - - - SILT Y SAND WITH GRAVEL (SNI): -ray-brow wet, mediu.n dense, fine -Brined, occasion31 cobhies to 9 inches ir. ;ongest dimension. (F1Li.) - grades to moist. -' ^ SILT WITH SAND (ML): gray with red -brown mottling, moist, mc&rr. stiff, low plass, city, trace organics observed (rootlets). (YOUNGER ALLUVIUM) grades to v.let - 1orades to gray, sa.TY SAND (SNI): gray, wet, toose, fine-grai.ne2 (YOUNGER ALLUVIUTA) Test pit was completed to a depth of 13 feet below ground surface. Groundwater was cneauntered ❑t a depth oC6 feet below ground surface during excavat'an Tcst pit was backfilled with excavated soil and tamped with backhoc shovel. Q DATE EXCAVATED' :il 1;2006 APPROYI1v7ATE ELEVATION: 21 M iLEVIi-'WFD BY:f. Reirart c + SAMPLE TYPE: � Bulk T Gr ah f� '5h' -.'6Y; »t,e a STP1-I STF1-2 20 LOGGFD BY: F. R--inat, EQUlNVFN`f: Backhoe OTHER TESTS+ *TESTS: WMo-slureCanrent(16f, D-Dn,Oer��i11'fP�ii, T1:=To:va;32, PD-PocketPeriet-omerer, G=Gram Sine, KT�EINFELDER Proposed Auto Body Shop SW Grady Way & Raymond Ave SW GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS Renton, Washington SOILS AND MATERIALS TESTING PROJECT N0.64923 TEST PIT LOG TP -1 Appendix A-4 V 15 O n. a, e ---,� � _ SOIL DESCRIPTION i Surracs: forest duff " � � z z Z � OTHER TESTS* �--- 0 --------------------------- - Topsoil (b inches thick). SM SILT Y SAND WITH GRAVEL (Sy1) Bray -brown, wet, medium dense, fine-grained, occasinnat cobbies to STPz I 8 inches in longest dimension. (FILL) - grades to moist. ' ML ----------------------- SILT WITH SAIND (ML): grey with red -brown STP2-2 mottling, moist, medium stiff, low plasticity, trace organics observed (rootlets). (YOUNGER ALLUVIUM) - slight groundwater seepage observed during excavation, grades to wet. grades to gray- S;M ------------------------- SILTY SAND (SM): gray, %vet, loose, Finc-grained. STP2-3 (YOUNGER ALLUVIUM) Test pit was cornpleted to a depth of 15 feet below ground surface, Groundwater was encountered at a deptn of 7 feel below ground surface during excavation. Test pit w:s barkfilled with excavated soil and tamped with backhoe shovel. DATE EXCAVATED: '.!I l,'2006 APPROXIMATE ELEVATION: 23 LOGGI D BY: F. Rdnait REVIEWED BYT. Feinart EQUIPMENT: Backhoe +SA.NTPLE TYPE- Bulk [) Grub jI Shelby Tube. L L W ■ ICLEINN ELDER GEOTECHNICAL AND ENWRONMENTAL ENGINEERS m S0IL5 AND MATERIALS TESTING PROJECT NO, 64923 *TESTS: M=Mcistr<re Cvnterit'%), D=13ry l�erSit} (pCf), Tv-Torvone, Pp=Pockel Penetrometer, G=C,rorn size, (72- % Pqrsin No. 100Sieve .4 -Afterbere Limits Proposed Auto Body Shop Appendix SW Grady Way c& Raymond Ave SW Renton, Washington A - 5 TEST PIT LOG TP -2 a I S» I II'i ML 5 71 SOIL DESCRIPTION �, ! Surface: t""ores[ du'f Topsoil �4 inches lhicc). SILT Y SAND VViIFH GRAVEL light -brown, wei, medium dense, fine-grained, with organics (rootlets and wood fragrr+entS). _ LILLJ- ---- ; SKIT WITH SAND (ML): light gray -brown, most with occasional lenses of wet silty sand observed in cuttings, medium st:fT, low plasticity, trace gravel, trace organics 05served {rootlets). (YOUNGER ALLUVIUM) - grades to wet, some sidewali sloughing observed during excavation. - grades to gray with red -brown mottling, grades to gray. 10 14 ' 'Test pit wm is cornpleted to a depth of 14 feet belnw zrowA surlace. Groundwater was encountered at a depth of 6.: feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shovel. DATE EXCAVATED: P1 IfZ06 APPRQXIMA !� E -ENATION: 23 REVfEWED BY:P. Rainart Sr ST ST LOCGISD BY: F. Reinart EQUOMENT: Backhoe SAMPLE TYPE:�� lh £!k T Grab H Ehe:lby Tube *TEST'S: ,V=.Moisture CantsMt�/), D=Dry Den.siry(pcl), TI—Torvane, 1 ] PD -Pocket lenoiromwer, G=Grain Sire, kn KLEINFELDERProposed Auto Body Shop Appendix GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SW Grady Way & Raymond Ave SW Renton, Washington A - 6 en SOILS AND MATERIALS TESTING g PROJECT NO.6492.3 �� TEST PIT LOG TP -3 0 ML 10 SLrfaGcl forest 6Uff ToLsoil(4 ir,chcs thickL _ SILT V4'tT}3 SAND (lv1L), gray -brown, vaet, medium stiff, low plasticity, organics observed (rootlets and 4eaf fragments), some side+wall sloughing during excavation. (YOUNGER ALLUVIUM) - grades to gray wth red -brown motri'.ng, trace organics (rootlets). - grades to we.. grades to gray. 13 F Test pit was eornpletcd to a depth of 13 feet below ground surface. Groundwater was encountered at a depth of 6.5 feet below ground surface during excavation. Test pit was nackfiiled with excavated soil and tamped with backhoe shave!. >a a STP4-1 1 19 STP4-2 STP4-3 OTHER TESTS* O DATE EXCAVATED: 1/11/2046 APPROXIMATE FLEVATiON: 22 LOGGED BY: F. Reinart Z: M PEVtFWED SY:F, Rc1Mar, EQUIPMENT: Backhoe + SAMPLE TYPE-�1 Bulk j[7 Groh rj Shelby Tube -'VESTS: y =Moimure C'onrenr,%), D=Dry Density I�c�, Tv=Tarvane, Uj If O �� Pp-, oekef Penelromerer, G-Grom Size, G2-% Fassinje NP. 200 MeveA-Alferberr Limits Proposed Auto Body Shop Appendix k"KLEINFELDER SW Grady Way & Raymond Ave SW F GEOTECHNICALSOILS NDAND MATERIIALS TES ANG GINEERS Renton, Washington A - 7 a Uj PROJECT 11Id. is49�3 TEST PIT LOG TP -4 SOIL DESCRIPTION 0. P Surface; forest duff R �> 0 10 II ML ToogoIL4inchestrick)____________ SILT Wlf_H'§XND (ML); gray -brown, wet, medium stiff, tow plasticity, organics observed (rootlets and tear fragments), sidewall sloughing during excavation. (YOUNGER ALLUVIUM) - grades to Dray with red -brown mottling, trace organics (rrpodtts). - grades to wet. - grades tc gray. Test pit was terminated at a depth of I I feet below ground surface because of excessive sloughing of the test pit sidewalls. Groundwater was encountered at a depth of 6 feet below ground surface during excavation Test pit was backfilled with excavated soil and tamped with backhoe shovel. G a� 00 OTHERTESTS* �¢D STPS-I S`fPS-2 l 2� DATE EXCAVATED: Ifl 112006 APPROXIMATE ELEVATION; 23 LOGOF:_D BY: F. Reinart REVIEWED BY:F. Reinart EQUIPMENT: Backhoe + SAMPLE TYPE:� Bulk � Grab n Shelby Tube u ■ KLEINFELDER GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS C:1 SOILS AND MATERIALS TESTING *TESTS: A4 Moislure Content %,-", D=Dq 1%ensuy{pcfl, 1 Torvane, PF=Pockel Penetrometer, G=Grain Size, G2=%PasSM N. 20QSieve, A-AflzrbCa L pmts Proposed Auto Body Shop Appendix SW Grady. Way & Raymond Ave SW A _ S Renton, Washington PROTECT NO. 64923 'FEST PIT LOG TP -5 ("KL INrL=- L DHR Bright People, Right Solutions. �y December 9, 2008 Kleinfelder Project No.: 91418 Washington State Auto Dealers Association 16000 Christensen Road, Suite 150 Tukwila, Washington 98188 ATTN: Mr. Kirk Robinson Subject: Findings Letter Limited Soil Characterization 621 SW Grady Way Renton, Washington Dear Mr. Robinson: 2405 140" Avenue NE, suite A101 Bellevue, Washington 98004 PI 425.562.4200 fl 425.562.4201 kleinfelder.com This letter presents Kleinfelder's findings from a limited soil characterization performed at the above -referenced address. In particular, the focus of this assessment was on the north face of a fill stockpile primarily located on a property south of the referenced address. This stockpile overlapped into an alley adjacent to the south side of the above -referenced address. This assessment was performed in accordance with our December 9, 2008, Work Order No. 3. FIELD EVALUATION AND SAMPLING Mr. Frank Reinart of Kleinfelder visited the site and visually evaluated the north face of the stockpile within the alley right-of-way limits. Mr. Reinart looked for areas of apparent soil contamination, as well as possible sources of soil contamination (i.e. drums, buckets, other waste containers, etc.), on the ground surface. Additionally, Mr. Reinart excavated a series of eight small test holes with hand tools to depths of 6 to 12 inches into the side of the stockpile to evaluate the fill material directly beneath the stockpile surface. No visible evidence of soil contamination was observed on the north surface of the fill stockpile. The fill material apparently consisted of a combination of silt and sand soil, 91418.2/SEABL231.doc Page 1 of 8 December 9, 2008 Copyright 2008 Kleinfelder crushed aggregate, organics (roots, logs and wood fragments), fragments of asphaltic concrete, and other scattered garbage and construction debris (i.e. tarp fragments, small pieces of wood, etc.). No documentation was available to Kieinfelder as to the origin of the fill material. Mr. Reinart collected three (3) composite soil samples from the north face of the fill stockpile within the alley right -of way. The locations of these samples are shown on Figure 1. Samples were submitted to OnSite Environmental, Inc. The following laboratory tests were performed for each sample: • NWTPH Dx (diesel/heavy oil) • RCRA 8 Metals (arsenic, barium, cadmium, chromium, lead, mercury, selenium, silver) Polycyclic Aromatic Hydrocarbons (PAHs) The laboratory tests were selected based on conditions observed at the site (specifically the presence of asphaltic concrete debris) and our experience regarding common contaminants that might be encountered in fill exported from construction or development sites. FINDINGS The following tables summarize the results of our laboratory testing. The complete laboratory results are included as an attachment to this letter. TABLE 1: NWTPH Dx SAMPLE NUMBER ANALYTE TEST RESULT (mglkg)2 MINIMUM CLEAN-UP STANDARD (mg/kg)' Diesel Heavy Oil FDR -E-12042008 35 290 2,000 FDR -C-12042008 ND 410 2,000 FDR -W-12042008 ND 68 2,000 Notes= 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 91418.2/SEA8L231.doc Page 2 of 8 December 9, 2008 Copyright 2008 Kleinfelder TABLE 2: PAHs per EPA 8270D/SIM — SAMPLE FDR -E-12042008 ANALYTE TEST RESULT (mg/kg) 2 MINIMUM CLEAN-UP STANDARD (mg/kg)1 Naphthalene ND 5 mg/kg for sum of Naphthalene, 1- Methylnaphthalene, and 2 - Methylnaphthalene 2 -Methylnaphthalene ND 1 -Methylnaphthalene ND Acenaphthylene ND Acenaphthene ND Fluorene ND NV Phenanthrene 0.022 Anthracene ND 24,000 (MTCA B) Fluoranthene 0.037 3,200 (MTCA B) Pyrene 0.040 2,400 (MTCA B) Benzo[a]anthracene 0.016 TEF -corrected cPAH concentration of 0.1 mg/kg Chrysene 0.028 Benzo[b]fluoranthene 0.034 Benzo[k]fluoranthene 0.0093 Benzo[a]pyrene 0.028 1ndeno(1,2,3-c,d)pyrene 0.016 Dibenz[a,h]anthracene ND Benzo[g,h,i]perylene 0.032 Notes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available_ If test results in table were ND, no clean-up level is included. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 3. NV = No Washington State Department of Ecology MTCA clean-up standard for this analyte 4. TEF = Toxicity Equivalent Factor calculation used to compare compound concentrations to MTCA Method A clean-up level for Benzo[a]pyrene. 91418.2l5EA8L231.doc Page 3 of 8 Deoember 9, 2008 Copyright 2008 Kleinfeider TABLE 3: PAHs per EPA 8270D/SIM — SAMPLE FDR -C-12442008 ANALYTE TEST RESULT (mg/kg) 2 MINIMUM CLEAN-UP STANDARD (mg/kg)1 Naphthalene ND 5 mg/kg for sum of Naphthalene, 1- Methylnaphthalene, and 2 - Methylnaphthalene 2 -Methylnaphthalene ND 1 -Methylnaphthalene ND Acenaphthylene ND Acenaphthene Fluorene ND ND Phenanthrene 0.038 NV Anthracene 0.010 24,000 (MTCA B) Fluoranthene 0.073 3,200 (MTCA B) Pyrene 0.073 2,400 (MTCA B) Benzo[a]anthracene 0.031 TEF -corrected cPAH concentration of 0.1 mg/kg Chrysene 0.054 Benzo[b]fluoranthene 0.064 Benzo[k]fluoranthene 0.023 Benzo[a]pyrene 0.053 1 ndeno(1,2,3-c,d)pyrene 0.031 Dibenz[a,h]anthracene 0.016 Benzo[g,h,i]perylene 0.052 NV Notes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available. If test results in table were ND, no clean-up level is included. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 3. NV =No Washington State Department of Ecology MTCA clean-up standard for this analyte 4. TEF = Toxicity Equivalent Factor calculation used to compare compound concentrations to MTCA Method A clean-up level for Benzo[a]pyrene. 91418.2l5EABL231,doc Page 4 of 8 December 9, 2008 Copyright 2008 Kleinfelder TABLE 4: PAHs per EPA 8270D/SIM — SAMPLE FDR -W-12042008 ANALYTE TEST RESULT (mg/kg) 2 MINIMUM CLEAN-UP STANDARD (mglkg)1 Naphthalene ND 5 mg/kg for sum of Naphthalene, 1- Methylnaphthalene, and 2 - Methylnaphthalene 2 -Methylnaphthalene ND 1 -Methylnaphthalene ND Acenaphthylene Acenaphthene ND ND Fluorene ND Phenanthrene ND Anthracene ND Fluoranthene ND Pyrene ND Benzo[a]anthracene ND TEF -corrected cPAH concentration of 0.1 mg/kg Chrysene ND Benzo[b]fluoranthene 0.0070 Benzo[k]fluoranthene ND Benzo[a]pyrene ND Indeno(1,2,3-c,d)pyrene ND Dibenz[a,h]anthracene ND Benzo[g,h,i]perylene 0.0081 Notes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available_ If test results in table were ND, no clean-up level is included. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 1 NV = No Washington State Department of Ecology MTCA clean-up standard for this analyte 4. TEF = Toxicity Equivalent Factor calculation used to compare compound concentrations to MTCA Method A clean-up level for Benzo[a]pyrene, 91418.2YSEABL231.doc Page 5 of 8 December 9, 2008 Copyright 2008 Kleinfelder TABLE a: RCRA 8 METALS per EPA 6010D/7471A — SAMPLE FDR -E-12042008 ANALYTE TEST RESULT (mglkg) 2 MINIMUM CLEAN-UP STANDARD (mglkg)' Arsenic ND Barium 78 16,000 (MTCA B) Cadmium ND Chromium (total) 32 2,000 Lead 12 250 Mercury Selenium Silver ND ND ND 49 Notes.- 1. otes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available. If test results in table were ND, no clean-up level is included. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 3. NV =No Washington State Department of Ecology MTCA clean-up standard for this analyte TABLE 6: RCRA 8 METALS Der EPA 6010D/7471A — SAMPLE FDR -C-12042008 ANALYTE TEST RESULT (mg/kg) 2 MINIMUM CLEAN-UP STANDARD (mg/kg)l Arsenic ND Barium 80 16,000 (MTCA B) Cadmium ND Chromium (total) 30 2,000 Lead 18 250 Mercury Selenium Silver ND ND ND Notes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available. If test results in table were ND, no clean-up level is included. 2_ ND =Not Detected; Concentrations lower than the test method detection limits. 3_ NV = No Washington State Department of Ecology MTCA clean-up standard for this analyte 91418.215EA8L231.doc Page 6 of 8 December 9, 2008 Copyright 2008 Kleinfelder TABLE 7: RCRA 8 METALS per EPA 6010D/7471A — SAMPLE FDR -W-12042008 ANALYTE TEST RESULT (mg/kg) 2 MINIMUM CLEAN-UP STANDARD (mg/kg)1 Arsenic ND Barium 51 16,000 (MTCA B) Cadmium ND Chromium (total) 25 2,000 Lead 6.7 250 Mercury ND ND ND Selenium Silver Notes: 1. Based on Washington State Department of Ecology MTCA A clean-up standards for unrestricted - use development, unless otherwise indicated. MTCA B clean-up standards indicated where no MTCA A standards are available. If test results in table were ND, no clean-up level is included. 2. ND = Not Detected; Concentrations lower than the test method detection limits. 3. NV = No Washington State Department of Ecology MTCA clean-up standard for this analyte CONCLUSIONS Based on the analytical results, concentrations in the surficial soil of the north face of the fill stockpile were either below Washington State Department of Ecology MTCA A clean-up standards for un -restricted use development, or were below MTCA B clean-up standards for analytes that had no MTCA A clean-up standard associated with them. LIMITATIONS The limited environmental site assessment described herein does not represent a comprehensive evaluation of the entire stockpile, and was limited to the sampling interval and depths indicated in this letter. It has been our experience that undocumented fill stockpiles are not homogenous and may have areas of soil contamination that are not apparent until soil removal activities are begun. Should evidence of soil contamination be encountered during removal of the fill soil stockpile from the alley right-of-way, Kleinfelder should be notified as soon as possible so additional sampling and testing can be performed. 91418.2ISEA8L231.doc Page 7 of 8 December 9, 2008 Copyright 2008 Kleinfelder If you have any questions or need further assistance, we do not hesitate to contact us at (425) 562-4200. Sincerely, KLEINFELDER WEST, INC. Frank D. Reinart, P.E. Geotechnical Engineer Ted W. Sykes Environmental Engineer 91418.2/SEA8L231 Aoc Page 8 of 8 December 9, 2008 Copyright 2008 Kleinfelder J I S. r7rr!-nos e Q U D - J F J co LU c� C 0 4 9" LL a D f } Y z ti W 0 LL cr3 W 2 a W�� a Y z C I Onsite Environmental Inc. 14648 NE 95th Street, Redmond, WA 98052 • (425) 883-3881 December 5, 2008 Frank Reinart Kleinfelder 2405 140'h Avenue NE Suite A101 Bellevue, WA 98005 Re: Analytical Data for Project Grady Way Alley Laboratory Reference No. 0812-037 Dear Frank: Enclosed are the analytical results and associated quality control data for samples submitted on December 4, 2008. The standard policy of OnSite Environmental Inc. is to store your samples for 30 days from the date of receipt. If you require longer storage, please contact the laboratory. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning the data, or need additional information, please feel free to call me. Sincerely, David Baumeister Project Manager Enclosures Onsite Environmental, Inc. 14648 NE 95'' Street, Redmond, WA 98852 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley Case Narrative 2 Samples were collected on December 4, 2008 and received by the laboratory on December 4, 2008. They were maintained at the laboratory at a temperature of 2°C to 6°C. General QA/QC issues associated with the analytical data enclosed in this laboratory report will be indicated with a reference to a comment or explanation on the Data Qualifier page. More complex and involved QA/QC issues will be discussed in detail below. OnSite Environmental, Inc. 14648 NE 95'" Street, Redmond, WA 98652 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 3 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley NWTPH-Dx Date Extracted: 12-4-08 Date Analyzed: 12-4-08 Matrix: Soil Units: mg/kg (ppm) Client ID: FDR -E-12042008 FDR -612042008 FDR -W-12042008 Lab ID: 12-037-01 12-037-02 12-037-03 Diesel Range: 35 ND ND PQL: 29 29 26 Identification: Diesel Range Organics --- --- Lube Oil Range: 290 410 68 PQL: 59 58 53 Identification: Lube Oil Lube Oil Lube Oil Surrogate Recovery o-Terphenyl: 88% 77% 78% Flags: N,Y Y Y OnSite Environmental, Inc. 14648 NE 95' Street, Redmond, WA 96052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 4 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley NIAITPH-Dx METHOD BLANK QUALITY CONTROL Date Extracted: 12-4-08 Date Analyzed: 12-4-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: MB1204S1 Diesel Range: ND PQL: 25 Identification: --- Lube Oil Range: ND PQL: 50 Identification: --- Surrogate Recovery o-Terphenyl: 76% Flags: y Onsite Environmental, Inc. 14648 EVE 95'h Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 5 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley NWTPH-Dx DUPLICATE QUALITY CONTROL Date Extracted: 12-4-08 Date Analyzed: 12-4-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: 12-037-03 12-037-03 DUP Diesel Range: ND ND POL: 25 25 RPD: N/A Surrogate Recovery o-Terphenyl: 78% 85% Flags: Y Y OnSite Environmental, Inc. 14648 NE 95`" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to wham it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley PAHs by EPA 8270D/SIM Matrix: Soil Units: mg/Kg I -t QnSite Environmental, Inc. 14648 NE 950 Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date Date Analyte Result PQL Method Prepared Analyzed Flags Client ID: FDR -E-12042008 Laboratory ID: 12-037-01 Naphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 2 -Methylnaphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 1 -Methylnaphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthylene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Fluorene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Phenanthrene 0.022 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Anthracene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Fluoranthene 0.037 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Pyrene 0.040 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]anthracene 0.016 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Chrysene 0.028 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[b]fluoranthene 0.034 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[k]fluoranthene 0.0093 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]pyrene 0.028 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Indeno(1,2,3-c,d)pyrene 0.016 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Dibenz[a,h]anthracene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo{U,h,i]perylene 0.032 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Surrogate: Percent Recovery Control Limits Nitrobenzene -d5 81 39-110 2-Fluorobiphenyl 77 41-107 Terphenyl-d14 76 .54-126 QnSite Environmental, Inc. 14648 NE 950 Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley PAHs by EPA 827QD/SIM Matrix: Soil Units: mg/Kg 7 OnSite Environmental, Inc. 14648 NE 95" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date Date Analyte Result POL Method Prepared Analyzed Flags Client 1D: FDR -C-12042008 Laboratory ID: 12-037-02 _ Naphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 2 -Methylnaphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 1 -Methylnaphthalene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthylene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthene ND 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Fluorene ND 0.0078 EPA 82701SIM 12-4-08 12-5-08 Phenanthrene 0.038 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Anthracene 0.010 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Fluoranthene 0.073 0.0078 EPA 82701SIM 12-4-08 12-5-08 Pyrene 0.073 0.0078 EPA 82701SIM 12-4-08 12-5-08 Benzo[a]anthracene 0.031 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Chrysene 0.054 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[b]fluoranthene 0.064 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[k]fluoranihene 0.023 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]pyrene 0.053 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Indeno(1,2,3-c,d)pyrene 0.031 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Dibenz[a,hjanthracene 0.016 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Benzo[c),h,i]perylene 0.052 0.0078 EPA 8270/SIM 12-4-08 12-5-08 Surrogate: Percent Recovery Control Limits Nitrobenzene -d5 85 39-110 2-Fluorobiphenyl 74 41-107 Terphenyl d 14 71 54-126 OnSite Environmental, Inc. 14648 NE 95" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley' PAHs by EPA 8270D/SIM Matrix: Soil Units: mg/Kg 8 OnSite Environmental, Inc. 14648 NE 95"' Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date Date Analyte Result POL Method Prepared Analyzed Flags_ Client ID: FDR -W-12042008 _Laboratory ID: 12-037-03 Naphthalene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 2 -Methylnaphthalene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 1 -Methylnaphthalene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthylene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Fluorene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Phenanthrene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Anthracene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Fluoranthene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Pyrene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]anthracene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Chrysene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Benzo[b]fluoranthene 0.0078 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Benzo[k]fluoranthene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]pyrene ND 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Indeno(1,2,3-c,d)pyrene ND 0.0074 EPA 8270/SIM 12-4-08 12-5-08 Dibenz[a,h]anthracene NO 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Benzo ,h,i a lene 0.0081 0.0070 EPA 8270/SIM 12-4-08 12-5-08 Surrogate: Percent Recovery Control Limits Nitrobenzene -'5 85 39-110 2-Fluorobtphenyl 76 41-107 Terphenyl-d14 76 54-126 OnSite Environmental, Inc. 14648 NE 95"' Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley PAHs by EPA 8270D/SIM METHOD BLANK QUALITY CONTROL Matrix: Soil Units: mg/Kg Date Date Analyte Result POL Method Prepared Analyzed Flags Laboratory ID: MB1204S1 Naphthalene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 2 -Methylnaphthalene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 1 -Methylnaphthalene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthylene NO 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Acenaphthene NO 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Fluorene NO 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Phenanthrene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Anthracene ND 0.0067 EPA 8270/51M 12-4-08 12-5-08 Fluoranthene ND 0.0057 EPA 8270/SIM 12-4-08 12-5-08 Pyrene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]anthracene ND 0.0067 EPA 82701SIM 12-4-08 12-5-08 Chrysene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Benzo[b]fluoranthene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Benzo[k]fluoranthene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Benzo[a]pyrene ND 0.0067 EPA 82701SIM 12-4-08 12-5-08 Indeno(1,2,3-c,d)pyrene NO 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Dibenz[a,h]anthracene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Benzo[g,hJ]perylene ND 0.0067 EPA 8270/SIM 12-4-08 12-5-08 Surrogate. Percent Recovery Control Limits Nitrobenzene -d5 77 39-110 2-Fluorobiphenyl 71 41-107 Terpheny�d14 82 54-126 OnSite Environmental, Inc. 14648 NE 95'" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley PAHs by EPA 8270D/SIM SB/SBD EQUALITY CONTROL Matrix: Sail Units: mg/Kg 10 Onsite Environmental, Inc. 14648 NE 95'" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Percent Recovery RPD Analyte Result 5 €ke Level Recovery Limits RPD Limit Flags SPIKE BLANKS Laboratory ID: SB1204S1 SB SBD SB SBD SIB SBD Naphthalene 0.0548 0.0569 0.0833 0.0833 66 68 45-94 4 24 Acenaphthylene 0.0650 0.0650 0.0833 0.0833 78 78 51 -104 0 25 Acenaphthene 0.0640 0.0642 0.0833 0.0833 77 77 53-103 0 21 Fluorene 0.0689 0.0690. 0.0833 0.0833 83 83 57-107 0 19 Phenanthrene 0.0671 0.0685 0.0833 0.0833 81 82 61 - 104 2 17 Anthracene 0.0700 0.0697 0.0833 0.0833 84 84 58-102 0 14 Fluoranthene 0.0747 0.0753 0.0833 0.0833 90 90 69-109 1 27 Pyrene 0.0748 0.0754 0.0833 0.0833 90 91 71 - 114 1 27 Benzo[a]anthracene 0.0652 0.0658 0.0833 0.0833 78 79 61-123 1 18 Chrysene 0.0712 0.0725 0.0833 0.0833 85 87 66-124 2 19 Benzo[b]fluoranthene 0.0773 0.0773 0.0833 0.0833 93 93 72-114 0 26 Benzo[k]fluoranthene 0.0774 0.0769 0.0833 0.0833 93 92 70-115 1 17 Benzo[a]pyrene 0.0708 0.0708 0.0833 0.0833 85 85 57-104 0 18 Indeno(1,2,3-c,d)pyrene 0.0786 0.0797 0.0833 0.0833 94 96 63-121 1 20 Dibenz[a,h]anthracene 0.0786 0.0795 0.0833 0.0833 94 95 62-125 1 15 Benzo 9,h,€ perylene 0.0761 0.0773 0._0.833 0.0833 91_ _ 93 64-117 2 21 Surrogate: Nitrobenzene -d5 80 79 39-110 .2-Fluorobiphenyl 75 73 41-107 Terphenyl-d14 81 81 54-126 Onsite Environmental, Inc. 14648 NE 95'" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 11 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 60108/7471A Date Extracted: 12-4-08 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: 12-037-01 Client ID: FDR -E-12042008 Analyte Method Result PQL Arsenic 60106 ND 12 Barium 60106 78 2.9 Cadmium 6010B ND 0.59 Chromium 6010E 32 0.59 Lead 6010B 12 5.9 Mercury 7471 A ND 0.29 Selenium 6010E ND 12 Silver 601 OB ND 0.59 OnSite Environmental, Inc. 14648 NE 95'" Street, Redmond, WA 98052 (425) 883-3681 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 12 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 60106/7471 A Date Extracted: 12-408 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab I D: 12-037-02 Client ID: FDR -C-12042008 Analyte Method Result PQL Arsenic 60108 ND 12 Barium 60108 80 2.9 Cadmium 6010E ND 0,58 Chromium 6010E 30 0.58 Lead 60106 18 5.8 Mercury 7471A ND 0.29 Selenium 6010E ND 12 Silver 6010B ND 0,58 Onsite Environmental. Inc. 14648 NE 95" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 13 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 601 OB/7471 A Date Extracted: 12-4-08 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: 12-037-03 Client ID: FDR -W-12042008 Analyte Method Result POL Arsenic 60108 ND 11 Barium 6010E 51 2.6 Cadmium 60106 ND 0.53 Chromium 6010E 25 0.53 Lead 60108 6.7 5.3 Mercury 7471 A ND 0.26 Selenium 6010E ND 11 Siler 6010B ND 0.53 Onsite Environmental, Inc. 14648 NE 95"' Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 14 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 60108/7471 A METHOD BLANK QUALITY CONTROL Date Extracted: 12-4-08 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: MB1204S1&MB1204S2 Analyte Method Result PPL Arsenic 60106 ND 10 Barium 6010B ND 2.5 Cadmium 6010E ND 0.50 Chromium 60106 ND 0.50 Lead 60106 ND 5.0 Mercury 7471 A ND 0.25 Selenium 60106 ND 10 Silver 60108 ND 0.50 OnSite Environmental, Inc. 14648 NE 95`" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. 15 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 60108/7471 A DUPLICATE DUALITY CONTROL Date Extracted: 12-4-08 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: 12-010-27 Flags Onsite Environmental, Inc. 14648 NE 95' Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Sample Duplicate Analyte Result Result RPD PQL Arsenic ND ND NA 10 Barium 99.5 101 1 2.5 Cadmium ND ND NA 0.50 Chromium 31.1 35.7 14 0.50 Lead ND ND NA 5.0 Mercury ND ND NA 0.25 Selenium ND ND NA 10 Silver ND ND NA 0.50 Flags Onsite Environmental, Inc. 14648 NE 95' Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley TOTAL METALS EPA 601 OB17471 A MS/MSD QUALITY CONTROL Date Extracted: 12-4-08 Date Analyzed: 12-4&5-08 Matrix: Soil Units: mg/kg (ppm) Lab ID: 12-010-27 OnSite Environmental, Inc. 14648 NE 95`h Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Flags iL: Spike Percent Percent Analyte Level MS Recovery MSD Recovery RPD Arsenic 100 93.2 93 96.6 97 4 Barium 100 200 100 205 105 3 Cadmium 50 48.2 96 47.9 96 1 Chromium 100 131 100 134 99 1 Lead 250 233 93 233 93 0 Mercury 0.50 0.497 99 0.494 99 1 Selenium 100 92.2 92 96.1 96 4 Silver 25 22.4 88 21.7 87 1 OnSite Environmental, Inc. 14648 NE 95`h Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. Flags iL: 17 Date of Report: December 5, 2008 Samples Submitted: December 4, 2008 Laboratory Reference: 0812-037 Project: Grady Way Alley % MOISTURE Date Analyzed: 12-4-08 Client ID Lab ID FDR -E-12042008 12-037-01 FDR -C-12042008 12-037-02 FDR -W-12042008 12-037-03 OnSite Environmental, Inc. 14648 NE % Moisture 15 14 Street, Redmond, WA 88052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. W. Onsite Environmental Inc. Data Qualifiers and Abbreviations A - Due to a high sample concentration, the amount spiked is insufficient for meaningful MSIMSD recovery data. B - The analyte indicated was also found in the blank sample. C - The duplicate RPD is outside control limits due to high result variability when analyte concentrations are within five times the quantitation limit. E - The value reported exceeds the quantitation range and is an estimate. F - Surrogate recovery data is not available due to the high concentration of coeluting target compounds. H - The analyte indicated is a common laboratory solvent and may have been introduced during sample preparation, and be impacting the sample result. I - Compound recovery is outside of the control limits. J - The value reported was below the practical quantitation limit. The value is an estimate. K - Sample duplicate RPD is outside control limits due to sample inhomogeneity. The sample was re -extracted and re -analyzed with similar results_ L - The RPD is outside of the control limits. M - Hydrocarbons in the gasoline range are impacting the diesel range result. M1 - Hydrocarbons in the gasoline range (toluene-napthalene) are present in the sample. N - Hydrocarbons in the lube oil range are impacting the diesel range result. O - Hydrocarbons indicative of heavier fuels are present in the sample and are impacting the gasoline result. P - The RPD of the detected concentrations between the two columns is greater than 40. Q - Surrogate recovery is outside of the control limits. S - Surrogate recovery data is not available due to the necessary dilution of the sample. T - The sample chromatogram is not similar to a typical U - The analyte was analyzed for, but was not detected above the reported sample quantitation limit. U1 - The practical quantitation limit is elevated due to interferences present in the sample. V - Matrix Spike/Matrix Spike Duplicate recoveries are outside control limits due to matrix effects. W - Matrix Spike/Matrix Spike Duplicate RPD are outside control limits due to matrix effects. X - Sample extract treated with a mercury cleanup procedure. Y - Sample extract treated with an acid/silica gel cleanup procedure. Z - ND - Not Detected at PQL PQL - Practical Quantitation Limit RPD - Relative Percent Difference OnSite Environmental, Inc. 14648 NE 95`" Street, Redmond, WA 98052 (425) 883-3881 This report pertains to the samples analyzed in accordance with the chain of custody, and is intended only for the use of the individual or company to whom it is addressed. co C) E KLEI NFELDER 2405 l40`° Avenue NE Suite A101 Bellevue, WA 98005 (425) 562-4200 (425) 562-4201 fax January 28, 2008 Kleinfelder Project No. 91418 Washington State Auto Dealers Association 16000 Christensen Road, Suite 150 Tukwila, WA 98188 Attention: Ms. Vicki Giles Fabr6 Subject: Preliminary Geotechnical Evaluation Proposed Development 621 South Grady Way Renton, Washington Dear Ms. Giles Fabre, This letter report presents Kleinfelder's preliminary geotechnical evaluation for the proposed Washington State Auto Dealers Association (WSADA) development located at ' 621 South Grady Way in Renton, Washington. Previously, Kleinfelder performed a geotechnical study of the site for the Pharr Company. The results of that study were summarized in our previous Geotechnical Engineering Report, dated March 10, 2006. We were initially contacted by Mr. Kirk Robinson of The Robinson Company, who requested Kleinfelder to perform this preliminary evaluation for the new site development proposed by WSDA. Authorization for our services was provided by WSADA via signed work order dated December 21, 2007. The attached Vicinity Map (Figure 1) shows the location of the site, and Site & Exploration Plan (Figure 2) shows the proposed new building layout. This letter report supplements the previous geotechnical report issued by Kleinfelder for this site and should only be used in conjunction with this previous report. PROJECT DESCRIPTION Our understanding of the proposed project is based on information provided by Mr. Robinson dated December 11, 2007, and preliminary drawings provided to us via electronic mail dated January 21, 2008. We also reviewed a preliminary site plan and utility schematic prepared by WH Pacific dated January 18, 2008, and a foundation plan prepared by Integrus Architecture dated January 9, 2008. We understand that the 91418/SEA8R008.doc Page 1 of 10 January 28, 2008 , Copyright 2008 Kleinfelder proposed project will involve construction of a 6,200 square foot single -story building, along with a fully developed approximately 34,000 square foot site comprising parking areas, landscaping, a retaining wall, and a below -grade storm detention vault. We understand the finish floor of the building will be 22.5 feet elevation, which is close to the existing ground surface elevation across the site. Thus, site grades will likely not be changed significantly from present grades. Based on the foundation plan provided to us, the preliminary concept being considered is a pile -supported building with a structural floor slab, using 18 -inch diameter augercast piles installed to about 35 feet depth. PURPOSE AND SCOPE OF SERVICES The purpose of our evaluation was to provide preliminary geotechnical opinions and recommendations for site design, based on Kleinfelder's previous evaluation of the site to allow WSADA to make an informed judgment concerning purchase of the property. Our scope of services for this project is outlined in our proposal dated December 21, 2007, and included a review of a previous geotechnical study, geotechnical evaluations, and preparation of this letter report. Our scope of services did not include additional site explorations or laboratory testing. SITE CONDITIONS Surface Conditions As part of our scope of services for this evaluation, we visited the site to check for changes made to the site since the issue of our March 10, 2006 Report. Based on the reconnaissance performed on January 23, 2008, the site conditions have not changed significantly from those we observed during our initial evaluation. The subject site is presently undeveloped and moderately vegetated with a mix of trees, bushes, and grass. Garbage and construction debris piles were observed in sporadic locations throughout the site, though most of the construction debris appeared to be located in the western portion of the site. Subsurface Conditions Kleinfelder explored the site for a previous site development concept in 2006 by advancing two borings and six test pits across the site, as shown on Figure 2. The two borings were drilled to a depth of 44 feet, and the test pits were excavated to depths ranging from 11 to 14 feet below the 2006 ground surface. Exploration logs and laboratory testing data from the previous report are attached to this letter. It should be 91418/SEA8ROOB.doc Page 2 of 10 January 28, 2008 Copyright 2008 Kleinfelder noted that the previous site explorations used for this preliminary evaluation were not performed specific to the currently proposed development. Based on these previous explorations, the subsurface soil profile generally consists of a thin layer of topsoil overlying fill, younger alluvium, and older alluvium. A more detailed description of each soil unit is provided below: Topsoil: Topsoil was encountered at the ground surface at the locations of each of the test pits and borings performed during the 2006 field exploration. Topsoil thickness ranged from approximately 3 to 6 inches. Fill. Fill was encountered beneath the topsoil at the locations of B-2, TP -1 through TP- F, and TP -6. The layer extends to a depth of approximately 1 to 6 feet below ground surface (bgs). This layer consists of loose to medium dense silty sand with varying amounts of gravel, organics, and construction debris. Younger Alluvium: Younger alluvium is encountered beneath the fill or topsoil at the location of each of the borings and test pits performed during our 2006 field exploration. The test pits were terminated within this layer. Based on the two borings advanced at this site, this layer extends to depths ranging from approximately 13.6 feet below present grade in the east portion of the project site to approximately 24 feet in the west portion of the project site. The younger alluvium represents relatively low-energy channel deposits and consists of soft to medium stiff silt with sand or very loose to loose silty sand. Excavation sidewall sloughing was observed during test pit excavations into this layer. Older Alluvium: Older alluvium was encountered beneath the younger alluvium at the locations of both borings. Both borings were terminated within this layer. The older alluvium represents relatively high-energy channel deposits and consists of medium dense to very dense sand with gravel. Groundwater was generally encountered during the 2006 site investigation at depths ranging between 6 and 9 feet below ground surface, which corresponds to approximate elevations ranging from 12 to 17 feet MSL. These measured groundwater levels at this site will likely fluctuate seasonally, and can generally be anticipated to be highest during the wetter winter and spring months and lower during the drier summer months. It should be noted that Kleinfelder did not perform a hydrogeologic evaluation at this site. The annual variability in groundwater depth at this site has not been measured. 914181SEA8R008.doc Page 3 of 10 January 28, 2008 Copyright 2008 Kleinfelder CONCLUSIONS AND PRELIMINARY RECOMMENDATIONS The following paragraphs present our conclusions and preliminary design recommendations for use by you and your consultants on this project. Based on the previous explorations performed by Kleinfelder in 2006, and our understanding of the proposed project, it is our opinion the proposed development is feasible at the subject site. Due to the presence of a relatively shallow groundwater table and soft, potentially liquefiable, and compressible soils, shallow foundations are not recommended for this project. Instead, we recommend that the proposed building be supported on a deep foundation system, with structural floor slabs. A summary of preliminary geotechnical considerations for developing the site is provided below. These preliminary recommendations supplement the previous geotechnical report issued by Kleinfelder for this site and should be used in conjunction with the recommendations provided in this previous report. Applicabiffty of 2006 Borings With regard to the proposed development, the coverage of Kleinfelder's past site explorations appears to be reasonable to evaluate the near surface soil conditions across the site. However, the two deep exploration borings are located between 40 and 80 feet away from the building, so no borings are located within the building footprint. Although this information may be suitable for a preliminary feasibility study, it does not provide adequate subsurface characterization for final design. In order to adequately identify the subsurface conditions at the new building location, we recommend that two additional borings be completed within the new building footprint prior to final design. These additional borings will help confirm the anticipated depth to older alluvium and provide additional information related to the design capacities and required pile penetration lengths. In addition, one of the additional borings should be completed as a piezometer to allow observation of groundwater levels, including seasonal fluctuations. Foundations We understand the current foundation design concept includes augercast foundations 18 inches in diameter and installed to 35 feet. Based on the previous two borings drilled at the site, the older alluvium is en countered at 18 to 24 feet below present site grades at the east and west ends of the site, respectively. The proposed 35 -foot depth will provide the previously recommended minimum penetration of 10 feet into the older alluvium bearing layer. However, local variations of the depth to bearing layer may exist within unexplored areas of the site, such as the proposed building location. Final pile 814181SEMR008.doc Page 4 of 10 January 28, 2008 Copyright 2008 Kleinfelder embedment depths should therefore be reevaluated based on additional explorations advanced at the building location as part of final design. Kleinfelder previously recommended Geopierso as another support method wherein shallow foundations could be used following the ground improvement. Geopierse can be a cost-effective alternative to a deep foundation system, such as piles, at sites where a suitable bearing layer can be identified within 20 to 30 feet of the existing ground surface. However, Geopier0 installation may be difficult at this project site because of the existing depth to the older alluvium and the relatively shallow groundwater table. If desired, a cost -benefit analysis could be performed for the two building support options, considering the site-specific conditions, in order to identify the most suitable support option for this particular site. Floor Slab The current concept provided by Integrus incorporates structural slabs with the pile supported foundations. This is in agreement with previous Kleinfelder's previous recommendations. Regardless of the deep foundation system chosen, concrete slab - on -grade floors should be designed as structural slabs and be supported in the same manner as the building. Site Grading and Earthwork The onsite fill and young alluvium are generally not suitable for use as structural fill, because of organic content, moisture content, and high to very high moisture sensitivity. Kleinfelder recommends the contract documents include unit costs for both export of on- site soil and import of the select fill recommended below During our 2006 site exploration, the backhoe utilized to excavate test pits sank into the soft surface soils and had to be moved with the aid of its bucket. We therefore anticipate very wet and/or soft surface soil conditions. A temporary working pad of a 12 -inch thick layer of 2-4 inch quarry spalls, or 18 inches of clean granular structural fill, may be needed to provide construction access and to protect the soil subgrade on all temporary/permanent roadways and in areas of foundation installation rigs and other heavy equipment. A separation geotextile should be used beneath the quarry spalls in areas of heavy traffic and in all future pavement areas to provide a separation barrier between the fine-grained subgrade soils and the working pad material. Prior to placing the temporary work pad, the exposed soils should be evaluated by a Kleinfelder representative. Any areas that are excessively soft or yielding should be over- 914181SEMR008.doc Page 5 of 10 January 28, 2008 Copyright 2008 Kleinfelder excavated as directed by the Kleinfelder representative and backfilled with properly compacted structural fill. Based on our current project understanding, site grades may be raised by 2 to 3 feet. Fill placed to raise site grades will likely induce some settlement in the underlying soft compressible soils. Unless the fill can be placed as a preload prior to pile installation, this will require deep foundations be designed for downdrag forces. Further testing and analysis of the settlement characteristics of the soft soil layers may be performed during the additional exploration phase, in order to identify the time frame required for preload settlement to occur. Utilities connecting with the building structure should be designed to accommodate movement between the structure and the non -pile supported adjacent structures or surrounding areas. In addition, pavements and sidewalks at the project site may require some maintenance or leveling over the life of the project. The contractor should be responsible for the safety of personnel working in utility trenches. Dewatering will be required for utility trenches that extend below the groundwater level. We recommend all utility trenches, but particularly those greater than 4 feet in depth, be supported in accordance with state and federal safety regulations. Pavements We anticipate pavement subgrade will be prepared by constructing a working granular blanket overlying approved subgrade. Prior to placing base rock the subgrade should be re-evaluated by a Kleinfelder representative to allow identification and correction of any soft or unstable areas. A pavement design was not included in our scope of services, but can be provided once final design traffic loading is available. Buried Structures and Dewatering Based on our current understanding of the proposed development, no basement levels are planned for the building. However, the storm water detention vault located west of the building is shown at a base depth about 8 feet below present site grades. Based on groundwater conditions observed during our 2006 exploration, this vault will be partially constructed below the groundwater level. Given the relatively shallow penetration (1 to 2 feet) below the groundwater level and the fine-grained nature of the site soils at this level, we anticipate that internal system of ditches, sump holes, and pumps will be adequate to temporarily dewater the excavations during construction. A 6 to 12 inch bearing layer of quarry spalls or clean crushed rock may be required to provide a stable 914181SEA8R008.doc Page 6 of 10 January 28, 2008 Copyright 2008 Kleinfelder base for the structure. We recommend that a Kleinfelder representative be allowed to evaluate the condition of the excavation base to assess the need for a bearing pad at the time of construction. Should deeper excavations be required (more than 2 feet below the groundwater table), we recommend that a dewatering study be performed to evaluate if a deeper dewatering system is required, and to identify anticipated quantities and flow rates for dewatering design. Kleinfelder can provide construction dewatering planning and design services for an additional fee, if desired. It should be noted that Kleinfelder has not installed any groundwater monitoring wells at this project site at the time of this study. However, we recommend that such wells be installed as a part of the final exploration and design phase to assist in developing a construction dewatering plan, if needed. It should be noted that the proposed below -grade structure may be submerged for part or all of the year, based on the shallow groundwater levels observed during our field exploration. The below -grade structures for the proposed development should be designed for hydrostatic forces and should be waterproofed, if required to maintain a dry vault condition. Seismic Design The following seismic design criteria should be used for the design of structures constructed at the project site. In accordance with Section 1615 of the 2003 IBC and based on the results of the standard penetration tests performed at the site, a Site Class of a is appropriate_ Based on our previous study, the loose, saturated sandy/silty soils at this site are susceptible to earthquake -induced liquefaction. In our opinion, supporting the proposed structure and floor slabs on auger -cast concrete piles that bear into the dense older alluvium below the liquefiable soils will adequately mitigate the potential effects of liquefaction hazards on the building. However, we estimate liquefaction may result in limited differential settlement on the order of 1 to 3 inches within the parking lot and other areas surrounding the structure. 914181SEA8R408_doc Page 7 of 10 January28, 2008 Copyright 2008 Kleinfelder Additional Services We recommend Kleinfelder be retained to provide the following additional services related to final design of the project: • Perform additional site borings in the building area to allow confirmation of the depth to the older alluvium and estimate pile driving requirements; • Prepare a supplemental geotechnical report which will include final recommendations for foundation design, site earthwork, excavations, dewatering, settlement estimates, augercast pile foundation design, liquefaction mitigation measures, and pavement design • Review of project plans and specifications for conformance to the geotechnical design requirements; • Observations and testing during site preparation, working blanket installation, earthwork, structural fill, pile foundation installation, and pavement section placement; • Testing and inspection of concrete, masonry, structural steel, fireproofing, and roofing materials; • Consultation as may be required during construction. LIMITATIONS The preliminary conclusions and recommendations contained in this report are based on past field explorations performed by Kleinfelder at the site, and our understanding of the proposed project. The investigation was performed using a mutually agreed upon scope of services. It is our opinion that this study was a cost-effective method to evaluate the potential geotechnical concerns for the new project concept. Kleinfelder should be retained to provide final design geotechnical recommendations once the site grading, layout and structural loads are available. The soils data used in the preparation of this report were obtained from test pits and exploratory borings completed in the spring of 2006. It is possible that variations in soil and groundwater conditions exist between the points explored, or that the soil or groundwater conditions have changed over time. The nature and extent of these variations may not be evident until construction occurs. If soil or groundwater conditions are encountered at this site that are different from those described in this report, our firm should be immediately notified so that we may make any necessary revisions to our recommendations. In addition, if the scope of the proposed project, locations of 91418/3EA8R008.doc Page 8 of 10 January 28, 2008 Copyright 2008 Kleinfelder facilities, or design building loads change from the descriptions given in this report, our firm should be notified. The scope of our services does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. This report has been prepared for use in evaluating the feasibility of development of the subject property by the WSADA in accordance with the generally accepted standards of practice at the time the report was written. No warranty, express or implied, is made. This report may be used only by the WSADA and their design consultants and only for the purposes stated within a reasonable time from its issuance, but in no event should this time exceed 12 months from the date of the report. Land or facility use, site conditions (both on- and off-site), regulations, advances in man's understanding of applied science, and/or other factors may change over time and could materially affect our findings and may require additional work. Therefore, this report should not be relied upon after 12 months from its issue. Kleinfelder should be notified if the project is delayed by more than 12 months from the date of this report so that a review of site conditions can be made, and recommendations revised if appropriate. Any party other than the WSADA or their design consultants who wishes to use this report shall notify Kleinfelder of such intended use. Based on the intended use of the report, Kleinfelder may require that additional work be performed and that an updated report be issued. It is the responsibility of the WSADA to see that all parties to the project including the designer, contractor, subcontractors, etc., are made aware of this report in its entirety. The use of information contained in this report for bidding purposes should be done at the contractor's option and risk. Further guidelines and information on this geotechnical report can be found in the ASFE publication entitled Important Information About Your Geotechnical Engineering Report, which is attached for your reference to this report. 914181SEA81R008.doc Page 9 of 10 January 28, 2008 Copyright 2008 Kleinfelder We appreciate the opportunity to provide review services on this project. If you have any questions regarding the contents of this proposal or require additional information, please call us at (425) 562-4200. Respectfully submitted, KLEINFELDER WEST, INC. Scott Ward, P.E. Senior Geotechnical Engineer Enclosures: Figure 1 -Vicinity Map D(FhRES WW 01 Rolf Hyllseth, P.E., L.G. Senior Geotechnical Engineer Figure 2 - Site & Exploration Plan Previous Boring Logs (B-1 through B-2) Previous Test Pit Logs (TP -1 through TP -6) Previous Soil Laboratory Results (1 Sieve Analysis, 1 Atterberg Limits) Important Information About Your Geotechnical Engineering Report Distribution: WSADA (3) Attn: Ms. Vicki Giles Fabre The Robinson Company (1) Attn: Mr. Kirk Robinson 914181sEA8R008.doc Page 10 of 10 Copyright 2008 Kleinfelder KL[INFi;LD[R 2401 140th Avenue NE, Suite A101, Bellevue, WA 98005 January 28, 2008 (425) 562-4200 (425) 562-4201 fax N t Projectlil Site wey o Me, R� Silly 16M St _ SW 1BIh.$ 3 [nan.-urlacrx inaamai pe -k ' � A 5 Copynghl 1AAS-2601 Mi—so0 Corp. -1its aoppirers An IVIS reserved. http:!fww Microsofl.comlmapp int ® Copyright 2000 by Geographic Oa1a Techcomgy, ino All •Ig Ms reserved. G 2000 Ilavlgalion iechn loges. All rghts -esarved w1 Copyright 2000 by L�mpusearch Micromarketing Cala and Syslems Ltd. SW 191 SL. Vicinity Map k"KLEINFELDER Proposed WSADA Development 621 Southwest Grady Way PROJECT NO. 91418 January2008 Renton, Washington FIGURE I c c o M X L X o m L Q � � Q ! Q A) q ananoAV1 %B&VL6A:O 3113 QVO _ 'S33bX 03H3V11V Al OReweyoguNUOld :Se6ewl :830M U3H3V11V APPENDIX A FIELD EXPLORATION Soil samples were collected from the borings at 5 -foot intervals using Standard Penetration Test (SPT) sampling techniques (ASTM D1586). The SPT consisted of driving a 1 -3l8 -inch inside -diameter split spoon sampler a distance of 18 inches into the bottom of the boring. The sampler was driven with a 140 -pound hammer falling 30 inches. The number of blows required to drive the sampler each of three 6 -inch increments was recorded on the boring logs. The number of blows required for the last 12 inches of penetration is called the standard penetration resistance (N -value). This value is an indicator of the relative density of granular soils or the consistency of fine- grained soils. Soil samples were collected from the test pits at changes in material type. Soil samples collected during the field exploration were classified in accordance with ASTM D2487. All samples were sealed in plastic bags to limit moisture loss, labeled, and returned to our laboratory for further examination and testing. The boring and test pits were monitored by our geologist/engineer who examined and classified the materials encountered, obtained representative soil samples, and recorded pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater occurrence. Upon completion of drilling, the borings were backfilled with a combination of native soil and bentonite chips. Soil classifications were made in the field in accordance with the Unified Soil Classification System, presented on Appendix A-1. Sample classifications and other related information were recorded on the boring and test pit logs, which are included in this appendix. The stratification lines, shown on the individual logs, represent the approximate boundaries between soil types; actual transitions may be either more gradual or more severe. The conditions depicted are for the date and location indicated only, and it should not necessarily be expected that they are representative of conditions at other locations and times. SOIL CLASSIFICATION CHART NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS EGrady ed Mato Body Shap ;APNDIXWay &Raymond Ave 5 SOIL CLASSIFICATION LEGENDton, Washington ,,, KLEINFELDER 23 March 2006 MAJOR DIVISIONS SYMBOLS TYPICAL GRAPH LETTER DESCRIPTIONS CLEAN s s • i 0 oSol WELL -GRADED GRAVELS, GRAVEL - GRAVELS �O a 0� GW SAND MIXTURES, 0% TO 1590 GRAVEL • FINES AND GRAVELLY (LITTLE OR N4 FINES) 00 000 °O 0a GP POORLY -GRADED GRAVELS, GRAVEL -SAND MIXTURES, OOO °° 0 0a 0% TO SOILS 0 0 15% FINES COARSE GRAVELS WITH 0 o ° a ° ° GM SILTY GRAVELS, SILTY GRAVEL - GRAINED MORE THAN 509 FINES o ° SAND MIXTURES SOIL OF COARSE 000 O FRACTION RETAINED ON N0. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) GC CLAYEY GRAVELS, CLAYEY GRAVEL - SAND MIXTURES SAND CLEAN SANDS SW WELL -GRADED SANDS, GRAVELLY SANDS, 0% TO 157 FINES MORE THAN 50% AND Of MATERIAL IS LARGER THAN NO. SANDY (LITTLE OR NO FINES) .'.'.'.'...'..' . PDORLY-GRADE6 SANDS, 200 SIEVE SIZE SOILSSP GRAVELLY SAND, D% TO 15% ....... • FINES SANDS WITH :; .. ..; SM SILTY SANDS, SILTY SAND --GRAVEL MORE E SDS OF COAFRACTION FINES MIXTURES 4A55� ON NO. (APPRECIABLE AMOUNT OF FINES)s� CLAYEY SANDS, CLAYEY SAND - GRAVEL MIXTURES INORGANIC SILT'S AND VERY FINE CDNENDSRRILAML CLAYEY FINE CLOR AYEY SILTS WITH SLIGHT PLASTICITY FINE SILTS GRAINED LIQUID LIMIT AND LESS THAN 50 CL INORGANIC CLAYS OF LOW TO AGR GRAVELLY CLAS, SOIL CLAYS SANDYIC CLAYS, LEAN CLAYS _-"- ---------- OL ORGANIC SILTS AND ORGANIC - SILTY CLAYS OF LOW PLASTICITY MORE THAN 50% INORGANIC SILTS, MICACEDUS OR OF MATERIAL IS SMALLER THAN NO. MH DIATOMACEOUS FINE SAND OR 200 SIEVE SIZE SILTY SOILS SILTS AND LIQUID LIMIT CH INORGANIC CLAYS OF HIGH CLAYS GREATER THAN 54 PLASTICITY OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY HIGHLY ORGANIC SOILS ::::: PT PEAT. HUMUS, SWAMP SOILS WITH HIGH ORGANIC CONTENTS NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS EGrady ed Mato Body Shap ;APNDIXWay &Raymond Ave 5 SOIL CLASSIFICATION LEGENDton, Washington ,,, KLEINFELDER 23 March 2006 35 40- 44 SOIL DESCRIPTION 24 S1-7 ® SPT (2" OD) Split Spoon Core , Shelby Grab ® Sample Tube - grades to medium- to coarse-grained, no W ELL/PIEZOr j X E: silty sand observed. Q S 2 ;4 W GS CONSTRUCTION '� Q � SW Grady Way & Raymond Ave SW yW W v .� Renton, Washington A -2b NMENTAL ENGINEERS GEOTECHNICALSOILS 35 AND MATERIOALS TESTING 4 A.9 zAj j 04 015.5 B-1 PAGE 2 of O iy o < a ez 24 X o 3 35 40- 44 SOIL DESCRIPTION tsormg was completed to a depth of 44 feet below ground surface. Groundwater was encountered at a depth of 7 feet below ground surface during drilling. Boring was backfilled with a mixture of cuttings and bentonite chips. 4 24 S1-7 ® SPT (2" OD) Split Spoon Core , Shelby Grab ® Sample Tube - grades to medium- to coarse-grained, no 30 X 140 lbs (30" Dro ) silty sand observed. Q 37 o KU SW Grady Way & Raymond Ave SW Appendix o KLEINFELDER 31 SI -7 Renton, Washington A -2b NMENTAL ENGINEERS GEOTECHNICALSOILS 35 AND MATERIOALS TESTING BORING LOG cc 0 N PROJECT NUMBER: 64923 015.5 B-1 PAGE 2 of 2 51-4 24 X tsormg was completed to a depth of 44 feet below ground surface. Groundwater was encountered at a depth of 7 feet below ground surface during drilling. Boring was backfilled with a mixture of cuttings and bentonite chips. 4 *SAMPLER B Cal. (POD) Q TYPE Split; ® SPT (2" OD) Split Spoon Core , Shelby Grab ® Sample Tube C, No a Recover e Y a "DAMMER WEIGHT 304 lbs (30" Drop) 140 lbs (30" Dro ) Q Proposed Auto Body Shop o KU SW Grady Way & Raymond Ave SW Appendix o KLEINFELDER Renton, Washington A -2b NMENTAL ENGINEERS GEOTECHNICALSOILS AND MATERIOALS TESTING BORING LOG cc 0 N PROJECT NUMBER: 64923 B-1 PAGE 2 of I I 2 2. 30 DATE DRILLED: 2-7-06 LOGGED BY: F. Reinart REVIEWED BY: F. Reinart SURFACE ELEVATION (feet): 21.0 TOTAL DEPTH (feet): 44.0 DIAMETER OF BORING (in): 8 inches k"K.LEINFELDER GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SOILS AND MATERIALS TESTING DRILLING METHOD: HSA DRILLER: Subterranen Drilling CASING SIZE: N/A Proposed Auto Body Shop SW Grady Way & Raymond Ave SW Renton, Washington BORING LOG B-2 Appendix A -3a PAGE I of 2 TESTING PROGRAM U.5.C.5. LABORATORY FIELD F w o WELL/PIEZO �; a� SOIL DESCRIPTION CONSTRUCTION ��� CF: Zu w 1 W H Z u�� ❑ 11 �� W 0 Surface: forest duff a Q TopsoI inchesthick)---------- 5M SILTY SAND (5M) light gray -brawn with orange -brown mottling, moist, dense, fine-grained, occasional construction debris 17.0 32 S24 observed in cuttings_ (FILL) 34 19 _ _ ML _ _ SILT WITH SAND (ML) light----- gray -brown with orange to red -orange mottling, moist to wet, medium stiff, low plasticity, thin (1 /8 to 1/4 inch thick) seam of brown peat, trace organics observed 2 S2-2 (rootlets), 0.25 to 0.5 tsf unconfined X compressive strength (pocket 2 penetrometer). 3 (YOUNGER ALLUVIUM) D - grades to wet. SM SILTY SAND (SM): gray, wet, very — loose, fine-grained, seams of gray sandy silt. 30.0 1 S2-3 (YOUNGER ALLUVIUM) 1 1 2 X 524 SM SILTY SAND (SM): gray, wet, loose, 1 fine-grained, trace organics (rootlets) - 2 (YOUNGER ALLUVIUM) 2 S2-5 i 2 6 SP ------------ SAND WITH GRAVEL (SP): gray to ; black, wet, medium dense, medium- to coarse-grained, trace silt. (OLDER ALLUVIUM) E 8 S2-6 - grades to dense, coarse-grained, no i4 observable silt in sampler. 19 30 DATE DRILLED: 2-7-06 LOGGED BY: F. Reinart REVIEWED BY: F. Reinart SURFACE ELEVATION (feet): 21.0 TOTAL DEPTH (feet): 44.0 DIAMETER OF BORING (in): 8 inches k"K.LEINFELDER GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SOILS AND MATERIALS TESTING DRILLING METHOD: HSA DRILLER: Subterranen Drilling CASING SIZE: N/A Proposed Auto Body Shop SW Grady Way & Raymond Ave SW Renton, Washington BORING LOG B-2 Appendix A -3a PAGE I of 2 30- 35 Ulf 44 - SOIL DESCRIPTION ® SPT (2" OD) Split Spoon TESTING PROGRAM 16 S2-7 - grades to very dense. 140 lbs (30" Drop) 29 U.S.C.S. LABORATORY FIELD 0 k%iKLEINFELDER 29 SW Grady Way & Raymond Ave SW WELLIPIEZO o F F: ra ZF h [: W, WIZ aw �a � p m x CONSTRUCTION � � � zW w L � � J 36 X 0 N PROJECT NUMBER: 64923 B_2 PAGE 2 of 2 0- 24 u� Oz Fy A aN W t 14 52-9 C C, 29 30- 35 Ulf 44 - SOIL DESCRIPTION s -i tsoring was completed to a depth of 44 feet below ground surface. Groundwater was encountered at a depth of 9 feet below ground surface during drilling. Boring was backfilled with a mixture of cuttings and bentonite chips. * SAMPLER Cal. (3"OD) TYPE Split Spoon ® SPT (2" OD) Split Spoon Core , Shelby m ® Grob Sample Tube ra 16 S2-7 - grades to very dense. 140 lbs (30" Drop) 29 X Proposed Auto Body Shap 0 k%iKLEINFELDER 29 SW Grady Way & Raymond Ave SW Appendix o 24.0 15 GINEER5 NGEOTECHNICALSOILS 52-8 BORING AND MATERIALS TESTING 36 X 0 N PROJECT NUMBER: 64923 B_2 PAGE 2 of 2 24 14 52-9 29 s -i tsoring was completed to a depth of 44 feet below ground surface. Groundwater was encountered at a depth of 9 feet below ground surface during drilling. Boring was backfilled with a mixture of cuttings and bentonite chips. * SAMPLER Cal. (3"OD) TYPE Split Spoon ® SPT (2" OD) Split Spoon Core , Shelby m ® Grob Sample Tube ra No Recovery "HAMMER WEIGHT 300 lbs (30 Dro } 140 lbs (30" Drop) Proposed Auto Body Shap 0 k%iKLEINFELDER SW Grady Way & Raymond Ave SW Appendix o Renton, Washington A 3b GINEER5 NGEOTECHNICALSOILS BORING AND MATERIALS TESTING LOG 0 N PROJECT NUMBER: 64923 B_2 PAGE 2 of 2 C m a 9L a C 6 M n 4 h a A 0- 5- W 10- 13 O a � dSurface: z a 0 un SOIL DESCRIPTION forest dull ate., ¢ LA w n`a, �+ V� z �z (•" � p OTHER TESTS* — Topsoil (6 inches thick)_ T SM SILT Y SAND WITH GRAVEL (SM): gray -brown, wet, medium dense, fine-grained, occasional cobbles to 8 inches in longest dimension. (FILL) - grades to moist. ML SILT WITH SAND (ML) gray with red -brown mottling, moist, medium stiff, low plasticity, trace organics observed (rootlets). (YOUNGER ALLUVIUM) STPI-1 20 - grades to wet, grades to gray. i STPI-2 SM SILTY SAND (SM): gray, wet, loose, fine-grained (YOUNGER ALLUVIUM) Test pit was completed to a depth of 13 feet below ground surface. Groundwater was encountered at a depth of6 feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shave]. DATE EXCAVATED: 1/11/2006 APPROXIMATE ELEVATION: 23 LOGGED BY: F. Reinart REVIEWED BYT. Reinart EQUIPMENT: Backhoe +SAMPLE TYPE: ® Bulk m Grob n Shelby Tube ■ I LEINFELDER GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS rn SOILS AND MATERIALS TESTING PROJECT NO. 64923 *TESTS: M=Moisture Conlenl(%). D=Dry Density(pefj, Tv=Torvone, Pp=Pocket Penetrometer, G=Groin Size, G2 =% Fassine No. 200 Sieve A =Atlerbere Limits Proposed Auto Body Shop Appendix SW Grady Way & Raymond Ave SW Renton, Washington A-4 T LOG TP -1 -7 El I 15 z o � _T SOIL DESCRIPTION Surface: forest duff Cnz �-+ z o OTHER TESTS* +SAMPLE TYPE: ®Bulk m Grab Shelby Tube — Topsoil (6 inches thick). Pp=Pocket Penetrometer, G=Graln Siie, SM G2=%Passim No. 20OSieve A=AlterbgLrg Limits SILT Y SAND WITH GRAVEL (SM): gray -brown, k4KLEINFELDER Proposed Auto Body Shop Appendix wet, medium dense, fine-grained, occasional cobbles to SW Grady Way & Raymond Ave y SW - a GEOTECHNICAL AND ENVIRONMENTAL, ENGINEERS SOILS AND MATERIALS TESTING 8 inches in longest dimension, STP2-1 Q PROTECT NO. 64923 (FILL) - grades to moist. ' ML SILT WITH SAND (ML) gray with red -brown STP2-2 mottling, moist, medium stiff, low plasticity, trace organics observed (rootlets). (YOUNGER ALLUVIUM) - slight groundwater seepage observed during excavation. - grades to wet. - grades to gray. SM SILTY SAND (SM): gray, wet, loose, fine-grained STP2-3 v (YOUNGER ALLUVIUM) t est pit was completed to a depth of 15 feet below ground surface. Groundwater was encountered at a depth of 7 feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shovel. a p DATE EXCAVATED: 1/1 1/2006 APPROXIMATE ELEVATION: 23 LOGGED BY: F. Reinart REVIEWED BY:F. Reinart EQUIPMENT-, Backhoe � a W +SAMPLE TYPE: ®Bulk m Grab Shelby Tube *TESTS: M=Moisture Content('/o), D=Dry Densio7(pcj), Tv=Torwme, g Pp=Pocket Penetrometer, G=Graln Siie, G2=%Passim No. 20OSieve A=AlterbgLrg Limits k4KLEINFELDER Proposed Auto Body Shop Appendix SW Grady Way & Raymond Ave y SW - a GEOTECHNICAL AND ENVIRONMENTAL, ENGINEERS SOILS AND MATERIALS TESTING Renton, Washington Q PROTECT NO. 64923 TEST PIT LOG TP -2 0 5- 10- 14 z SOIL DESCRIFTION Surface: forest duff Vo W4 n o OTHER TESTS* Topsoil (4 inches thickL ------------- -----------JSM SM SILT Y SAND WITH GRAVEL (SM); light -brown, wet, medium dense, fine-grained, with organics (rootlets and wood fragments). ML �FELiI---------- SILT WITH SAND (ML): light gray -brown, moist with occasional lenses of wet silly sand observed in cuttings, medium stiff, low plasticity, trace gravel, trace organics observed (rootlets). (YOUNGER ALLUVIUM) STP3-1 - grades to wet, some sidewall sloughing observed during excavation. - grades to gray with red -brown mottling. STP3-2 31 - grades to gray. I STP3-3 Test pit was completed to a depth of 14 feet below ground surface. Groundwater was encountered at a depth of 6,5 feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shovel. a DATE EXCAVATED: l/l 1/2006 APPROXIMATE ELEVATION: 23 LOGGED BY: F. Reinart O q REVIEWED BY:F_ Reinart EQUIPMENT: Backhoe e + SAMPLE TYPE: 7VI82e1k ( Grab n Shelby Tube *TESTS: M=Moisture Cauent(n/o), D=Dry Oensity(pcfi, Tv=Torvane, [jJ Pp=Pocker Penetrometer, G=Grain Size, G2=% Passing No. 200 Sieve A=Atterber Limits k'4KLEINFELDER Proposed Auto Body Shop Appendix GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SW Grady Way & Raymund Ave SWA-6 c, SOILS AND MATERIALS TESTING Renton, Washington PROJECT NO. 64923 D TEST PIT LOG TP -3 Q 5 FA 10 13 z o SOIL DESCRIPTION Surface: forest duff Cn W �z ., z 0 OTHER TESTS* T_ogsoil_L--esthick�________—___ J ML SILT WITH SAND (ML): gray -brown, wet, medium stiff, low plasticity, organics observed (rootlets and leaf fragments), some sidewall sloughing during excavation. (YOUNGER ALLUVIUM) STP4-1 14 - grades to gray with red -brown mottling, trace organics (rootlets). - grades to wet. STP4-Z grades to gray, STP4-3 I est pit was completed to a depth of 13 feet below ground surface. Groundwater was encountered at a depth of 6.5 feet below ground surface during excavation_ Test pit was backfilled with excavated soil and tamped with backhoe shovel. o Q DATE EXCAVATED: 1/1112006 APPROXIMATE ELEVATION: 22 REVIEWED BYT. Reinart � Q + SAMPLE TYPE: ® Bulk m Grob a Shelby Tube 0 N LOGGED BY: F. Reinart EQUIPMENT: Backhoe *TESTS: M=Moisture Content(°/), D=Dry Densiry(pgj), Tv=Torvane, Pp=Packet Penetrometer, G=Grain Size, IIIA "VE proposed Auto Body Shop Appendix GEOTECHNCCAL AND ENVIRONMENTAL, ENGINEERS SW Grady Way &Raymond Ave SW a nz SOILS AND MATERIALS TESTING Renton, Washington A-7 PROJECT NO. 64923 TEST PIT LOG TP -4 5 z 10 III z SOIL DESCRIPTION Surface: forest duff �, tn Z F O z o OTHER TESTS* o Topsoil(4inchesEhick___________. . ML SILT WITH SAND (ML): gray -brown, wet, medium stiff, low plasticity, organics observed (rootlets and leaf fragments), sidewall sloughing during excavation. (YOUNGER ALLUVIUM) STP5-I - grades to gray with red -brown mottling, trace organics (rootlets). - grades to wet. STP5-2 25 - grades to gray. Test pit was terminated at a depth of I I feet below ground surface because of excessive sloughing of the test pit sidewalk. Groundwater was encountered at a depth of 6 feet below ground surface during excavation, Test pit was backfilled with excavated soil and tamped with backhoe shovel. DATE EXCAVATED: 1/11/2006 APPROXIMATE ELEVATION: 23 LOGGED BY: F. Reinart REVIEWED BY:F. Reinart EQUIPMENT: Backhoe +SAMPLE TYPE: ® Bulk m GmbH Shelby Tube IMt KLEINFELDER GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SOILS AND MATERIALS TESTING PROJECT NO. 64923 *TESTS: M=Moisture Content(%), D=Diy Densiol(pc)j, Tv=Torvane, Pp=Pocket Penetrometer, G=Grain Sipe, G2=% FasshtQ No. 200 Sieve X=Atlerherz Limits Proposed Acta Body Shop Appendix SW Grady Way & Raymond Ave SW A r Renton, Washington TEST PIT C 5 0 10' 12 I est pu was terminatea at a aeptn of iz Leet below ground surface because of excessive sloughing of the test pit sidewalls. Groundwater was encountered at a depth of 6.5 feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shovel. DATE EXCAVATED: 1/11/2006 APPROXIMATE ELEVATION: 23 LOGGED BY. F. Reinart REVIEWED BY:F_ Reinart EQUIPMENT: Backhoe + SAMPLE TYPE: N Bulk m Grab n Shelby Tube *TESTS: M=Maislure Content(°%), D=Dry Densiry(pef), Tv= Toevane, Pp=Pockel Penetrometer, G=Grafn Size, k4KLEINFELDER G2—%Passin No. 200 Sieve R=Arrerber Limits Proposed Auto Body Shop Appendix GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SW Grady Way & Raymond Ave SW SOILS AND MATERIALS TESTING Renton, Washington A-9 PROJECT NO. 64923 TEST PIT LOG TP -6 SOIL DESCRIPTION Surface: forest duff CA i rW z U OTHER TESTS* Topsoil 3 inches thick). SM SILT Y SAND WITH GRAVEL (SM): light -brown, wet, medium dense, fine-grained, occasional brick ML , fragments. L —--------JFILL)----------/ SILT WITH SAND (ML): gray -brown, moist, medium stiff, low plasticity, trace organics observed (rootlets). STP6_1 14 (YOUNGER ALLUVIUM) grades to wet, some sidewall sloughing observed during excavation. - grades to gray with red=brown mottling. - grades to gray, sidewall sloughing observed to be more STP6-2 frequent. STP6-3 I est pu was terminatea at a aeptn of iz Leet below ground surface because of excessive sloughing of the test pit sidewalls. Groundwater was encountered at a depth of 6.5 feet below ground surface during excavation. Test pit was backfilled with excavated soil and tamped with backhoe shovel. DATE EXCAVATED: 1/11/2006 APPROXIMATE ELEVATION: 23 LOGGED BY. F. Reinart REVIEWED BY:F_ Reinart EQUIPMENT: Backhoe + SAMPLE TYPE: N Bulk m Grab n Shelby Tube *TESTS: M=Maislure Content(°%), D=Dry Densiry(pef), Tv= Toevane, Pp=Pockel Penetrometer, G=Grafn Size, k4KLEINFELDER G2—%Passin No. 200 Sieve R=Arrerber Limits Proposed Auto Body Shop Appendix GEOTECHNICAL AND ENVIRONMENTAL ENGINEERS SW Grady Way & Raymond Ave SW SOILS AND MATERIALS TESTING Renton, Washington A-9 PROJECT NO. 64923 TEST PIT LOG TP -6 APPENDIX B GEOTECHNICAL LABORATORY TESTING 1=>�i�rl�►1�:7�1� We conducted laboratory tests on several representative soil samples to better identify the soil classification of the units encountered and to evaluate the material's general physical properties and engineering characteristics. A brief description of the tests performed for this study is provided below. The results of laboratory tests performed on specific samples are provided at the appropriate sample depths on the individual boring logs. However, it is important to note that these test results may not accurately represent in situ soil conditions. All of our recommendations are based on our interpretation of these test results and their use in guiding our engineering judgment. Kleinfelder cannot be responsible for the interpretation of these data by others. In accordance with your requirements, the soil samples for this project will be retained a period of 6 months following completion of this report, or until the foundation installation is complete, unless we are otherwise directed in writing. B.2 SOIL CLASSIFICATION Soil samples were visually examined in the field by our representative at the time they were obtained. They were subsequently packaged and returned to our laboratory where they were reexamined and the original description checked and verified or modified. With the help of information obtained from the other classification tests, described below, the samples were described in general accordance with the Unified Classification System, ASTM Standard D2487. The resulting descriptions are provided at the appropriate locations on the individual boring and test pit logs, located in Appendix A, and are qualitative only. B.3 MOISTURE CONTENT Moisture content tests were performed on 10 samples obtained from the borings. The purpose of these tests is to approximately ascertain the in-place moisture content of the soil sample at the time it was collected. The moisture content is determined in general accordance with ASTM Standard D2216. The information obtained assists us by providing qualitative information regarding soil compressibility. The results of these tests are presented at the appropriate sample depths on the boring and test pit logs. B.4 GRAIN -SIZE DISTRIBUTION Detailed grain -size distribution analyses were conducted in general accordance with ASTM Standard D422 on 2 representative soil samples to determine the grain -size distribution of the on-site soil. The information gained from this analysis allows us to provide a detailed description and classification of the in-place materials. In turn, this information helps us to understand how the in-place materials will react to conditions such as seepage, traffic action, loading, potential liquefaction, and so forth. The results of these tests are presented in this Appendix. DuissL,d junjj )d 0 ca Q C v �'p 1� I �U d t�r't W In M O q N � I 0 _00 V3 U N C7 4 M � I O Q a 0 0 o O O 6 C7 O O O O Q 4 4 O O In" a00 O I'D in nt O Q O 0 Q Z 0 0 N C v �'p �U q N � 0 C V1 U C �U � � o U N Pe N m 'C �mssed luaaxad 0 0 Y O C -i — 2? cn O 0 VJ c Q a W V � v N z -y 0 W N W 'S 4 O i Q N 9 c Q a V � v 9 LIQUID LIMIT Trial No_ 1 2 3 Tare No_ A7 All A25 Wt_ Tare & Wet Soil 34.6 35.7 38.1 Wt. Tare & Dry Soil 30.5 31.3 32.9 Wt. Water (Ww) 4.1 4.4 5.2 Wt. Tare 20.2 20.3 20.5 Wt. Dry Soil (Ws) 10.3 11.0 12.4 Moisture Content (MC), % 39.8% 40.0% 41.9% No. of Blows 34 23 16 Adj. MC for 25 Blows, % 41.3% 39.6%39.7% SAMPLE DATA Sampled Location TP -3 Sample No. STP3-2 Depth 71 Soil Description Silt USCS 24.8 Specific Gravity 50.4 NATURAL M.C. Trial No. 1 Tare No. 16 Wt. Tare & Wet Soil 156.3 Wt. Tare & Dry Soil 131.5 Wt. Water (Ww) 24.8 Wt. Tare 50.4 Wt. Dry Soil (Ws) 81.1 Moisture Content (MC), % 30.6% PLASTIC LIMIT Trial No. 1 2 3 Tare No. A5 A23 A30 Wt. Tare & Wet Soil 26.2 26.7 26.3 Wt. Tare & Dry Soil 24.9 25.3 24.9 Wt. Water (Ww) 1.3 1.4 1.4 Wt. Tare 20.4 20.3 20.4 Wt. Dry Soil (Ws) 4.5 5.0 1 4.5 Moisture Content (MC), % 28.9% 28.0% 1 31.1% Plasticity Chart for Classification 70.0 60A CH or 014 50.0 40.0 30.0 CL or OL MH or OH 20.0 10.0 - ct. - ML ML or CL 0.0 , 0.0 20.0 40.0 60.0 80.0 100.0 120.0 Liquid Limit (LL) SUMMARY Plastic Limit 29.3% Liquid Limit 40.2% Natural MC 30.6% Plasticity Index 10.9% Ref, ASTM D 4315-84 D 2487-90 Note: All weights in grams (g) unless stated_ Kleinfelder Atterberg Limits Materials Testing Pharr Company L01A Bellevue, Washington Renton Auto body Shop Project Number Technician Approved Date Revised Date 64923 R. Crum 1 2116/2006 1 NA NA LIQUID LIMIT Trial No. 1 2 3 Tare No. 32 68 63 Wt. Tare & Wet Soil 37.7 42.0 37.6 Wt. Tare & Dry Soil 31.6 34.7 31.1 Wt. Water (Ww) 6.1 7.3 6.5 Wt. Tare 11.2 11.0 11.0 Wt. Dry Soil (Ws) 20.4 23.7 20.1 Moisture Content (MC), % 29.9% 30.8% 32.3% No. of Blows 29 26 19 Adi. MC for 25 Blows, % 1 30.4% 30.2%] 31.3% SAMPLE DATA Sampled Location TP -4 Sample No. STP4-1 Depth 2' Soil Description Silt USCS NIA Specific Gravity NIA NATURAL M.C. Trial No. j Tare No. B 1 Wt. Tare & Wet Soil 1071.0 Wt. Tare & Dry Soil 999.8 Wt. Water-(Ww) 71.2 Wt. Tare 629.0 Wt. Dry Soil (Ws) 370.8 Moisture Content (MC), % 19.2°!° PLASTIC LIMIT Trial No. x 2 3 Tare No. 56 60 71 Wt. Tare & Wet Soil 17.4 15.9 16.0 Wt. Tare & Dry Soil 16.1 14.9 14.9 Wt. Water (Ww) 1.3 1.0 1.1 Wt. Tare 11.0 10-9 10.9 Wt. Dry Soil (Ws) 5.1 4.0 4.0 Moisture Content (MC), % 25.5% 25.0% 27-5% Kleinfelder Materials Testing Bellevue, Washington Project Number Technician 64923 R. Crum Liquid Limit (LL) Atterberg Limits Pharr Company Renton Auto Body Shop Approved__T Date Revised 2/1612006 NA SUMMARY Plastic LMt 26.0% Liquid Limit 30.9% Natural MC 19.2% Plasticity Index Ref: ASTM D 4318-84 D 2487-90 Note: Atl weights in gums (g) unless stated. Date NA L02A Plasticity Chart for Classification 70-0 i 60.0 3 � I CH or OH 500 X 40.a I 30.0 CL or OL MH or OHI cs 20.0 I I I 10.0 CL - ML M Sample ML or CL 0.0 0.0 20.0 40.0 60.0 80.0 100.0 120.0 Kleinfelder Materials Testing Bellevue, Washington Project Number Technician 64923 R. Crum Liquid Limit (LL) Atterberg Limits Pharr Company Renton Auto Body Shop Approved__T Date Revised 2/1612006 NA SUMMARY Plastic LMt 26.0% Liquid Limit 30.9% Natural MC 19.2% Plasticity Index Ref: ASTM D 4318-84 D 2487-90 Note: Atl weights in gums (g) unless stated. Date NA L02A APPENDIX C CONSTRUCTION RECOMMENDATIONS This appendix presents a summary of our recommendations for the geotechnical aspects of construction. Our design recommendations and criteria presented in this report are based on these construction recommendations, therefore, these recommendations should be incorporated into the project specifications in their entirety. NOTE: This information shall not be used separately from this geotechnical report. CA GENERAL GEOTECHNICAL RECOMMENDATIONS C. 1.1 Geotechnical Engineer We recommend you retain Kleinfelder during construction to observe and test the geotechnical aspects of the contractor's work. This will allow us to compare the actual conditions encountered with those expected by this investigation and to modify our recommendations, if necessary. Kleinfelder should be present at the site on a full-time basis to check that the contractor's work conforms to the geotechnical aspects of the plans and specifications. The daily field reports and final report form an important record of construction. Observation and testing by the geotechnical engineer, however, should not in any way release the contractor from the responsibility of performing the work in such a manner as to provide a satisfactory job that meets the requirements of the project plans and specifications, or from meeting contractual obligations to the owner. C.9.2 Construction Site Safety Our scope of services did not include construction safety practices and this report is not intended to direct construction means, methods, techniques, sequences, or procedures, except as specifically described, and then only for consideration in design, not for construction guidance. The contractor should be made responsible for construction site safety and compliance with local, state, and federal requirements. C.1.3 Terms Terms used in this appendix are defined as follows: Percent Compaction is the required in-place dry density of the material, expressed as a percentage of the maximum dry density of the same material as determined by the Modified Proctor test method (ASTM D1557). Optimum Moisture Content is the moisture content (percent by dry weight) corresponding to the maximum dry density of the same material as determined by the Modified Proctor test method (ASTM D1557). Moisture -Sensitive Soil is soil containing more than 10 percent fines (silt- or clay -sized particles) based on the fraction passing the %-inch sieve. Structural Fill is fill material placed and compacted in areas that underlie structures or pavements. It should be compacted to the Percent Compaction (ASTM D1557) specified herein. It has a maximum particle size of 6 inches. C. 9.4 Quality Control Proper geotechnical observation and testing during construction is imperative to allow the geotechnical engineer the opportunity to verify assumptions made during the design process. The recommendations provided in this report are based on the assumption that an adequate program of tests and observations will be conducted during the construction phase in order to evaluate the compliance with our recommendations. C.2 EARTHWORK Earthwork consists of excavating, placing and compacting fill, utility backfilling, and all subsidiary work necessary to complete the grading of the developed areas to conform to the lines, grades, and slopes shown on the plans. Recommendations for sugrade preparation, excavation, structural fill, and utility backfilling are provided in Section 3.0 of this Geotechnical Report. C.3 DEWATERING AND DRAINAGE C.3.1 Dewatering Based on groundwater conditions observed during our exploration, we anticipate that dewatering will be required during construction of subgrade structures below the groundwater table, and may be necessary for the successful construction of Geopierse. A dewatering study and design, including anticipated quantities and flow rates, pump design, and discharge parameters and recommendations should be performed for this site once the anticipated site grades and structure depths are finalized. Kleinfelder has not installed any groundwater monitoring wells at this project site at the time of this report. However, we recommend that such wells be installed to assist in developing a dewatering study and design It should be noted that the proposed below -grade structures may be submerged for part or all of the year, based on the shallow groundwater levels observed during our field exploration. The below -grade structures for the proposed building should be designed to be waterproof and account for hydrostatic forces. Alternatively, permanent dewatering measures could be implemented at the site to maintain the groundwater level below the lowest grade of the building. However, in our experience this is costly and rarely practical. C.3.2 Drainage During construction, surface drainage not associated with the shallow groundwater table can be controlled by careful excavation practices. Typically, these include, but are not limited to, shallow upgrade perimeter ditches or low earthen berms, and temporary sumps in excavations to collect seepage and prevent water from damaging exposed subgrades. Drains should be included at the bottom of all temporary slopes to collect surface water flow from the slope and prevent it from flowing onto exposed building or pavement subgrades. All collected water should be conveyed under control to a positive and permanent discharge system, such as a storm sewer. Recommendations for permanent footing drains are provided in Section 3.3. All permanent drains should convey water under control to a positive and permanent discharge point well away from the structure. Roof downspouts should not be connected to footing drains, but should be tight lined separately to a positive discharge system. This will avoid the potential for roof debris to be washed into footing drains, possibly blocking them. Clean -outs should be provided for footing drains and the downspout tight lines. Drains should be backfilled with clean, free -draining gravel or crushed rock meeting the requirements of Section 9-03.12(4), Gravel Backfill for Drains, of the WSDOT Standard Specifications. Geotechnical Engineering Report Geotechnical Services Are Performed for Specific PurPoses, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical engineering study conducted for a civil engi- neer may not fulfill the needs of a construction contractor or even another civil engineer. Because each geotechnical engineering study is unique. each geotechnical engineering report is unique, prepared solelyfor the client. No one except you should rely on your geotechnical engineering report without first conferring with the geotechnical engineer who prepared it, And no one — not even you ---should apply the report for any purpose or project except the one originally contemplated. Read the Full Report Serious problems have occurred because those retying on a geotechnical engineering report did not read it all. Do not rely on an executive summary Do not read selected elements only. A Geotechnical Engineering Report Is Based on A Unique Set of Pr�ct-Sp�fic Factors Geotechnical engineers consider a number of unique, project -specific fac- tors when establishing the scope of a study. Typical factors include: the client's goals, objectives, and risk management preferences; the general nature of the structure involved. its sire, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates oth- erwise, do not rely on a geotechnical engineering report that was: • not prepared for you, • not prepared for your project, • not prepared for the specific site explored. or • completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect: • the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse, elevation; configuration, location, orientation, or weight of the proposed structure: composition of the design team, or project ownership. As a general rule, always inform your geotechnical engineer of project changes—even minor ones—and request an assessment of their impact. Geolechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed. Subsurface Conditions Can Change A geotechnical engineering report is based on conditions that existed at the time the study was performed. Do not rely on a geotechnical engineer- ing reportwhose adequacy may have been affected by: the passage of time; by man-made events, such as construction on or adjacent to the site; or by natural events, such as floods, earthquakes, or groundwater fluctua- tions. Always contact the geotechnical engineer before applying the report to determine if It is still reliable. A minor amount of additional testing or analysis could prevent major problems. Most Geotechnical lendings Are Professional Owens Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engi- neers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site Actual subsurface conditions may differ --sometimes significantly— from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide construction observation is the most effective method of managing the risks associated with unanticipated conditions A Report's Recommendations Are Mat Hnal Do not overrely on the construction recommendations included in your report. Those recorrrmendations are not final, because geotechnical engi- neers develop them priridpaily from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurra�tie cond�tiors revealed during „,nslructiori rile geulca+ Hflg,rl' i M,'D developei7 Y'U Jf report Ca.'!nof dssauie respor?srcJ,'ilry o" ha,ifi1 v for ri. 'Porus rec�wrlmerldaf.+cris if llraf Crgiriet�r j'�,5 Cr?,7Sf1`i1Cll�n u"�$$rVa+'i0r). A Geotechnical Engineering Report Is Subject to Misinterpretation Other design team members' misinterpretation of geotechnical engineering reports has resulted in costly problems Lower that risk by having your geo- technical engineer confer with appropriate menbers of the design team alter submitting the report. Also retain your geotechnical engineer to review pert nent elements of the design teams plans and specifications. Contractors can also misinterpret a geotechnica engineering report Reduce !hat risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing construction observation. Do Not Redraw the Engineer`s logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, butrecogrlize that separating fogs from the report can elevate risk Give Contractors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give con- tractors the complete geotechnical engineering report, but preface it with a clearly written letter of transmittal. In that letter. advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited, encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/or to conduct additional study to obtain the specific types of information they need or prefer A prebid conference can also be valuable. Be sure contrac- tors have sufficient lime to perform additional study Only then might you be it a position to give contractors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Read Responsibility Provisions Closely Some clients, design professionals, and contractors do not recognize that geotechnical engineering is tar less exact than other engineering disci- plines. This lack of understanding has created unreaFsfic expectations that nave Ic disa�linfry)rls c ar is a'd disprltes To hclp reduce the risk of sucf` ci.Morm-s. gE,,,NFchnlcai t.ng'nei'r5 i:gmmonlj Include a Variety o" exp anatcry pr;)vrslons in the it re;rnrts Sometimes aheled " imi-at ons' r?jany :}i Ihiisi' provisic)rs inrficate where geotevr.ica' engineers responsi- bdi!ies begin arid end to h{.Ip others reCognive their town respansioilities and risks. Bead these provisions clvst;ly Ask questi;,ns Your geotechnical engineer should respond fully and frankly. Geoenvironmental Concerns Are Not Covered The equipmenl. techniques. and personnel used to perform a geoenvircn- nargal study differ s griificantly from those I.Ised to perform a geofechnical study. For that reason_ a geotechnical engineering report does not usually relate any geoenvironmental findings conclusions, or recommendations, e.g . about the likelihood of encountering underground storage tanks or regulated conlaminants Urrarlticipated envirortrrientaf problems have led to numerous protea failures if you have not yet obtained your own geoen- vironmental information. ask your geotechnical consultant for risk man- agernent guidance. Do not rely on an enwonmental report prepared for someone else. Obtain Professional Assistance To Deal with Mall Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces To be effective, all such strategies should be devised for the express purpose of mold prevention, integrated into a com- prehensive plan, and executed with diligent oversight by a professional mold prevention consultant_ Because just a small amount of water or moisture can lead to the development of severe mold infestations, a num- ber of mold prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration. and similar issues may have been addressed as part of the geotechnical engineering study whose findings are conveyed in this report, the geotechnical engineer in charge of this project is not a mold prevention consultant: none of the services per- formed in connection with the geotechnical engineer's study were designed or conducted for the purpose of mold preven- tion. Proper implementation of the recommendations conveyed in this report will not of itself he sufficient to prevent mold from growing in or on the structure involved. Rely, on Your ASFE-Member Geotechncial Engineer for Additional Assistance Membership in ASFEiThe Best People on Earth exposes geotechnical engineers to a wide array of risk management techniques that can be of genuine benefit for everyone involved with a construction project. Confer with you ASFE-member geotechnical engineer for more information, ASFE the lest ieople me Earth 3811 Colesville Road/Suite G106, Silver Spr rg MD 20910 Telephone: 301?565-2733 f=acsimile 3011589-2017 e-mail: info@asfe.org wwwaste.org Copyright 2004 by ASFE. Inc, Duplication. reproduction, or copying o1 this document, in whole or in part, by any means whatsoever is strictly prohibited, except with ASFEs specific written permission. Excerpting, quormg. or otherwise extracting wording from this docoment is permitted only with the express writtenpermission of ASFE, and only for purposes of scholarly research or book review Only members of ASFE may use this document as a complement to or as an element of a geotechnical engineering report Any other firm individual. or other eerily that so uses this document without being an ASFE member could be committing negligent or intertfronat {'fraudu)ent} misrepresentation. I'GFROfi045 OM KLEINFELDER Prepared for: Pharr Company 114 1315 NE Bellevue, Washington 98005 Geotechnical Engineering Report Proposed Automotive Body Shop SW Grady Way and Raymond Avenue SW Renton, Washington Kleinfelder Project Number: 64923 Prepared by: Frank D. Reinart; E.I.T. Staff Geotechnical Engineer Marcus Byers; P.E. Geotechnical Division Manager Kleinfelder, Inc. 2405 - 140th Avenue NE Suite A101 Bellevue, VITA 98005 Phone: (425) 562-4200 Fax: (425) 562-4201 March 10, 2006 Copyright 2006 Kleinfelder, Inc. All Rights Reserved UNAUTHORIZED USE OR COPYING OF THIS DOCUMENT IS STRICTLY PROHIBITED BY ANYONE OTHER THAN THE CLIENT FOR THE SPECIFIC PROJECT. f� KLEINFE1.QER TABLE OF CONTENTS 1.0 INTRODUCTION AND SCOPE............................................................................'I 1.1 GENERAL. ............................................ 1.2 PROJECT DESCRIPTION.........................................................................1 1.3 PURPOSE AND SCOPE OF SERVICES...................................................2 1.4 REFERENCES........................................:..................................................3 1.4.1 WSDOT Standard Specifications................................................3 1.4.2 Agency/Association Initials.......................................................... 3 1.4.3 Common Abbreviations...............................................................3 1.5 LIMITATIONS., 4 2.0 SITE CONDITIONS...............................................................................................5 2.1 SURFACE..................................................................................................5 2.2 SUBSURFACE ................................... 5 2.2.1 Field Exploration ....... ................... .. 2.2.2 Soil Characterization.................................................... 6 2.3 GROUNDWATER......................................................................................6 3.0 CONCLUSIONS AND DESIGN RECOMMENDATIONS......................................7 3.1 GENERAL........................................................................................... .....7 3.2 SITE PREPARATION AND EARTHWORK................................................9 3.2.1 Demolition...................................................................................9 3.2.2 Site Stripping...............................................................................9 3.2.3 Site Grading and Excavation.....................................................10 3.2.4 Temporary excavations.............................................................11 3.2.5 Weather Considerations............................................................12 3.3 FOUNDATIONS.....................:.................................................................13 3.4 FLOOR SLABS........................................................................................15 3.5 SEISMIC DESIGN....................................................................................15 3.6 LATERAL EARTH PRESSURES.............................................................16 3.7 DEWATERING AND DRAINAGE..............................................................16 3.7.1 Dewatering...............................................................................16 3.7.2 Drainage....................................................................................17 3.8 UTILITIES... ....................................................... .... I I ........................ I ......... 18 4.0 ADDITIONAL SERVICES...................................................................................18 FIGURES Figure 1 -- Vicinity Map Figure 2 — Site Plan APPENDIX A Field Exploration B Laboratory Testing C Geotechnical Construction Recommendations D Important Information About Your Geotechnical Engineering Report 6492315EAR059Aoc Page i of i March S 0, 2Q06 Copyright 2005 Kieinfelder, Inc. 1.0 INTRODUCTION AND SCOPE 1.1 GENERAL k'q KLE[NFELDER This report presents the results of Kleinfelder, Inc.'s Neinfelder's) geotechnical engineering study conducted for the design and construction of the proposed automotive body shop, to be located at the southeast corner of the intersection between SW Grady Way and Raymond Avenue SW in Renton, Washington. The location of the project site can be found in Figure 1 — Vicinity Map. This report was prepared in accordance with our January 30, 2006 Contract Modification No.1 and our December 19, 2005 Revised Proposal. 1.2 PROJECT DESCRIPTION Our understanding of this project was developed based on telephone conversations with Mr. Tony Shapiro of AD Shapiro Architects, a September 22, 2005 Preliminary Site Plan, and an undated topographical drawing of the site that was emailed by Mr. Shapiro to Kleinfelder on December 6, 2005. We understand the proposed development will comprise a single -story, concrete - masonry building with a concrete floor. It is our understanding that foundation and floor slab types have not been selected at the time of this report. The building will be surrounded by landscaping and will have asphaltic -concrete paved parking lots located on the east and west sides of the site. The building footprint has been estimated at 14,204 square feet. The anticipated finished floor elevation for the building is approximately 26 feet above mean sea level (MSL). However, it is our understanding that repair bays set into the floor may have a lower anticipated finished floor elevation on the order of 13 to 16 feet MSL. Structural loads were not available at the time of this proposal. Once structural building loads have been developed for this building, they should be provided to Kleinfelder for our review, and to revise the recommendations provided herein, as necessary. Excavations for underground utilities are anticipated to be 10 feet below final grade, or less. We understand that the site grade will likely be raised approximately three feet. 649231SEA6RQ59.doc Page 1 of 18 March 10, 206 Copyright 2006 Kleinfelder, Inc. n KLEINFELDER 1.3 PURPOSE AND SCOPE OF SERVICES The purpose of our study was to explore subsurface conditions at the site as a basis for providing recommendations for site preparation, design, and construction of the proposed retail development. Specifically, our scope of services included.- Field ncluded: Field Exploration: We explored the soil and groundwater conditions at the site with a series of 6 test pits and 2 drilled borings. The exploration locations are shown in Figure 2 -- Site Plan. A more detailed description of the field exploration procedures, including the test pit and borings logs, is provided in Appendix A. • Laboratory Testing: We performed a total of 10 natural moisture content tests, 2 grain -size distribution tests, and 2 Atterberg limits tests on representative samples obtained from the borings and test pits. Laboratory test results are provided on the logs in Appendix A and/or as test reports in Appendix B_ Geotechnical Analysis: Engineering analyses were performed as a basis for development of recommendations regarding support of the proposed building and parking areas. Our design recommendations include the following: • Site preparation and grading including evaluation of the suitability of on-site soils for use as fill, gradation criteria for imported fill soils, and placement and compaction criteria of imported fill soils; • Earthwork performance for dry and wet weather conditions; Appropriate foundation types, including a preliminary evaluation of the feasibility of foundation alternatives including mat -style slab foundations, Geopierse, and drilled piles; • Allowable soil bearing pressures, minimum width and depth requirements, coefficient of friction and passive pressure to resist sliding, and estimates of foundation settlement for shallow foundations; • Support of concrete floor slabs and pavements, • Temporary and permanent site dewatering/drainage; • Lateral earth pressures for subsurface structures; and, international Building Code seismic site coefficients for use in structural analysis. 64923/SEA6R059.doc Page 2 of 18 March 10, 2006 Copyright 2006 Klainfelder, Inc. KFEI N F E L D E R Geotechnical Report: We prepared this report, presenting our findings, conclusions and recommendations. Section 2.0 describes site surface and subsurface conditions, and Section 3.0 presents our conclusions and design recommendations for this project. Recommendations specifically related to construction are included in Appendix C. 1.4 REFERENCES This section identifies, in brief, the standards, agency or association initials, and abbreviations referred to in this report. 1.4.1 WSDOT Standard Specifications Where possible, we refer in this report to sections of the 2006 Edition of the Washington State Department of Transportation (WSDOT) Standard Specifications for Road, Bridge, and Municipal Construction (henceforth referred to as the WSDOT Standard Specifications). 1.4.2 agency/Association Initials Agency or association standards are referred to by agency or association initials and refer to the latest -edition standards published by those agencies or associations. References in this report include the following: • ASTM - American Society for Testing and Materials: Annual Book of ASTM Standards • IBC - International Building Code • OSHA - Occupational Safety and Health Administration • WABO - Washington Association of Building Officials . • WISHA - Washington -Industrial Safety and Health Act; Washington State's occupational safety and health program • WSDOT - Washington State Department of Transportation 1.4.3 Common Abbreviations The following are common abbreviations used in the text of this report: • bgs - below ground surface KV - horizontal. -vertical (ratio) • MSF_ - Mean Sea Level pcf - pounds per cubic foot • pcf EFW - pounds per cubic foot equivalent fluid weight 6492WSEA6R059.doc Page 3 of 18 March 10, 2066 Copyright 2006 Kleinfelder, Inc. WAVE -B KLEI,NFFLDER psf - pounds per square foot psi - pounds per square inch 1.5 LIMITATIONS Recommendations contained in this report are based on the field explorations and our understanding of the proposed project. The investigation was performed using a mutually agreed upon scope of services. It is our opinion that this study was a cost- effective method to explore the subject site and evaluate the potential geotechnical concerns. The soils data used in the preparation of this report were obtained from test pits and exploratory borings completed for this study. It is possible that variations in soil and groundwater conditions exist between the points explored. The nature and extent of these variations may not be evident until construction occurs. if soil or groundwater conditions are encountered at this site that are different from those described in� this report, our firm should be immediately notified so that we may make any necessary revisions to our recommendations. in addition, if the scope of the proposed project, locations of facilities, or design building loads change from the descriptions given in this report, our firm should be notified. The scope of our services does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. This report has been prepared for use in evaluating the feasibility of development of the subject property by the Pharr Company in accordance with the generally accepted standards of practice at the time the report was written. No warranty, express or implied, is made. This report may be used only by the Pharr Company and their design consultants and only for the purposes stated within a reasonable time from its issuance, but in no event should this time exceed 12 months from the date of the report. Land or facility use, site conditions (both on- and off-site), regulations, advances in man's understanding of applied science, and/or other factors may change over time and could materially affect our findings and may require additional work. Therefore, this report should not be relied upon after 12 months from its issue. Kleinfelder should be notified if the project is 649231SEA6RO59.doc Page 4 of 18 March 10, 2046 Copyright 20D6 Kleinfelder, Inc. k" KLEINFFLDLR delayed by more than 12 months from the date of this report so that a review of site conditions can be made, and recommendations revised if appropriate. Any party other than the Pharr Company or their design consultants who wishes to use this report shall notify Kleinfelder of such intended use. Based on the intended use of the report, Kleinfelder may require that additional work be performed and that an updated report be issued. It is the responsibility of the Pharr Company to see that all parties to the project including the designer, contractor, subcontractors, etc., are made aware of this report in its entirety. The use of information contained in this report for bidding purposes should be done at the contractor's option and risk. Further guidelines and information on this geotechnical report can -be found in the ASFE publication entitled Important Information About Your Geotechnical Engineering Report, which is included for your reference in Appendix D of this report. 2.0 SITE CONDITIONS 2.1 SURFACE The subject site is presently undeveloped and moderately vegetated with a mix of trees, bushes, and grass. Garbage and construction debris piles were observed in sporadic locations throughout the site, though most of the construction debris appeared to be located in the western portion of the site. 2.2 SUBSURFACE 2.2.1 field Exploration Kleinfelder explored subsurface conditions at the site using a total of 6 test pits excavated with a backhoe (designated TP -1 through TP -6), and a total of 2 exploratory borings (designated B-1 and B-2) advanced with a truck -mounted drill rig utilizing continuous -flight, hollow -stem augers. The approximate locations of the test pits and boring are shown in Figure 2 - Site Plan. Exploration locations were obtained by taping distances from existing site features. More details of our field exploration and boring and test pit logs are provided in Appendix A of this report. 649231SE161R059_doc Page 5 of 18 March 10, 2006 Copyright 2005 Kleinfelder, Inc. M� KLEINFE=LDER 2.2.2 Soil Characterization Based on the conditions encountered, we characterized the soils and developed the general stratigraphic profile described below. Topsoil: Topsoil is encountered at the ground surface at the locations of all test pits and borings performed during our field exploration, This topsoil is approximately 3 to 6 inches thick. Fill: Fill is encountered beneath the topsoil at the locations of B-2, TP -1 through TP -3, and TP -6. The layer extends to a depth of approximately 1 to 5 feet below ground surface (bgs). This layer consists of loose to medium dense silty sand with varying amounts of gravel, organics, and construction debris. Younger Alluvium: Younger alluvium is encountered beneath the fill or topsoil at the location of all borings and test pits performed during our field exploration_ The test pits were all terminated within this layer. Based on the two borings advanced at this site, this layer extends to depths ranging from approximately 13.5 feet bgs in the east portion of the project site to approximately 24 feet bgs in the west portion of the project site. The younger alluvium represents relatively low-energy channel deposits and consists of soft to medium stiff silt with sand or very loose to loose silty sand. Excavation sidewall sloughing was observed during test pit excavations into this layer. Older Alluvium: alder alluvium is encountered beneath the younger alluvium at the locations of both borings. Both borings were terminated within this layer. The older alluvium represents relatively high-energy channel deposits and consists of medium dense to very dense sand with gravel. More detailed descriptions of subsurface conditions encountered at individual exploration locations are presented on the exploratory boring and test pit logs included in Appendix A - Field Exploration. This Appendix section also includes a description of exploration and sampling procedures. 2.3 GROUNDWATER Groundwater was generally encountered during our field exploration at depths ranging between 6 and 9 feet below ground surface, which corresponds to approximate elevations ranging from 12 to 17 feet MSL. 64923/SEA5R059.doc Page 6 of 18 March 10, 2006 Gopyright 2006 Kleinfelder, Inc. k%] KLEIN FEL DER Groundwater levels at this site will fluctuate seasonally, and can generally be anticipated to be highest during the wetter winter and spring months and lower during the drier summer months. It should be noted that Kleinfelder did not perform a hydrogeologic evaluation at this site. The annual variability in groundwater depth at this site has not been measured, General recommendations regarding dewatering and groundwater issues are provided herein. However, dewatering studies and/or designs should be performed for this site, and such studies and/or designs were not within Kleinfelder's scope of work at the time of this report. Since the proposed structure may be located partially and/or entirely below the fluctuating groundwater table both during and after construction, we strongly recommend that temporary and permanent, site-specific, dewatering and/or waterproofing measures be designed and developed as part of the proposed development. Kieinfelder can provide construction dewatering planning and design services for an additional fee, if desired. 3.0 CONCLUSIONS AND DESIGN RECOMMENDATIONS The following paragraphs present our conclusions and design recommendations for use by you and your consultants on this project. The site is suitable for the proposed developments provided that the recommendations contained herein are incorporated into the design and construction of the project. For satisfactory and successful construction of this project, these recommendations must be applied in their entirety and in conjunction with the construction recommendations provided in Appendix C. 3.1 GENERAL Based on the results of our exploration and analysis, we present the following general conclusions: As stated previously, since the proposed structure may be below the static groundwater table both during and after construction, we strongly recommend that both temporary and permanent, site-specific, dewatering measures be designed and developed as part of the proposed development. • The proposed building and concrete slab -on -grade floors should not be founded on a shallow foundation system, such as spread footings or a mat -style foundation that bears on the on-site fill and younger alluvium because these soils 649231sEA6R059.doc Page 7 of 18 March 10, 2006 Copyright 2006 Kleinfeldef, Inc- k'q KLEINFELDER are generally weak and compressible. The on-site fill and younger alluvium identified at the project site could be completely removed from the footprint of the proposed building. However, we do not recommend this alternative because it will entail cuts and fills on the order of 20 to 30 feet across the entire site, significant dewatering effort, and temporary excavation shoring. • A deep, foundation system, such as concrete auger -cast piles, is suitable for supporting the proposed building and concrete slab -on -grade floors. Once building loads are finalized, a pile foundation system can be designed to support the proposed building. Typically, the piles would be embedded a minimum of 10 feet into the very dense older alluvium. Final embedment depths should be evaluated as part of the deep foundation design. • Alternatively, the proposed building and concrete slab -on -grade floors can be founded on a shallow foundation system that is directly supported on Geopierso embedded into the older alluvium. Geopierse can be a cost-effective alternative to a deep foundation system, such as piles, at sites where a suitable bearing layer can be indentified within 20 to 30 feet of the existing ground surface. Final embedment depths should be evaluated as part of the Geopiero foundation design. However, Geopier° installation may be difficult at this project site because of the existing depth to the older alluvium and the relatively shallow groundwater table. Concrete slab -on -grade floors should be designed as structural slabs and be supported in the same manner and the building. • The onsite fill and young alluvium are generally not suitable for use as structural fill, because of organic content, moisture content, and high to very high moisture sensitivity. Consequently, it should be noted that the on-site soils at the project site are not suitable for reuse as structural fill. Therefore, the contract documents should include unit costs for both export of on-site soil and import of the select fill recommended herein. Pavement subgrades should be underlain by a minimum of 2 feet of firm and unyielding material. The existing surface soils are generally not suitable for supporting pavements. If site grades are not raised at least two feet, it will be 64923/SEA6RD59.doc Page 8 of 19 March 10, 2005 Copyright 2DD6 Kleinielder, Inc. k'q Ki_EINFELDER necessary to over -excavate the existing soils and replace with imported structural fill to achieve a 2 -foot thick layer of firm subgrade. During our site exploration, the backhoe utilized to excavate test pits sank into the soft surface soils and had to be moved with the aid of its Bucket. We recommend that grading plan incorporate construction of a working pad for foundation installation rigs and other heavy equipment. As a minimum, we recommend a 6 -inch thick layer of 2-4 quarry spalls overlain by 18 inches of structural fill. Fill placed to raise site grades will likely induce some settlement in the underlying soft compressible soils. Utilities should be supported with the building structure and designed to accommodate movement between the structure and the surrounding soils. In addition, pavements and sidewalks at the project site may require some maintenance or leveling over the life of the project. The remainder of this section discusses these conclusions and recommendations in greater detail, as well as other pertinent aspects of the project. 3.2 SITE PREPARATION AND EARTHWORK 3.2.9 . Demolition Demolition activities at the site should involve the removal of existing construction debris. Demolition debris generated at the project site should be properly disposed of off-site. 3.2.2 Site Stripping Topsoil stripping on the order of 6 inches should be performed at the project site prior to commencing general excavation activities. Stripped soil can be stockpiled for re -use in landscape areas. However, we recommend that a landscape architect test the soil and specify the required nutrient additives. Otherwise, the stripped organic -rich soil should be removed from the project site and disposed of properly. 645231SEA6R058.doc Page 8 of 18 March 10, 2006 Copyright 2006 Kleinfelder, Inc. �� KLEINFELDER 3.2.3 Site Grading and Excavation We anticipate that excavations of the fill and native on-site soils can be generally performed with conventional earthmoving equipment. As currently envisioned, site grading will consist generally of filling with excavations limited to below -grade repair bays. Temporary Work Pad Preparation: During our site exploration, the backhoe utilized to excavate test pits sank into the soft surface soils and had to be moved with the aid of its bucket. Because of the excessively soft surface soils and low-lying nature of the site that will tend to remain wet, we recommend construction of a temporary work pad across the entire project site. As a minimum, the work pad should consist of a 6 -inch thick layer of 2-4 inch quarry spalls overlain by 18 inches of structural fill. Pavement Subgrade Preparation.- Pavement reparation:Pavement subgrades should be underlain by a minimum of 2 feet of firm and unyielding material. The existing surface soils are generally not suitable for supporting pavements and we anticipate that if site grades are not raised at least two feet it will be necessary to over -excavate the existing soils and replace with imported structural fill to achieve the 2 -foot thick layer of firm subgrade. The temporary work pad can be incorporated into the 2 -foot layer of firm and unyielding material that must underlie all pavements provided it is proof rolled after the foundation equipment has demobilized. Subgrade Evaluation: Prior to placing structural fill to achieve a firm and unyielding pavement subgrade, or to construct the temporary work pad, the exposed soils should be evaluated by a representative of the geotechnical engineer. Any areas that are excessively soft or yielding should be over -excavated as directed by the representative of the geotechnical and backfilled with properly compacted structural fill. Structural Fill: Structural fill consists of the all material used to establish grade beneath pavements, sidewalks, or that will support structures Structural fill placed more than two feet below pavements during dry weather may consist of material conforming to the requirements of Section 9-03.14(3) Common Borrow of the WSDOT Standard Specifications. Structural fill placed during wet weather, within 2 feet of pavement subgrade or that will support structures should 64923/SEA6RD59.doc Page 10 of 18 March 1D, 2DD6 Copyright 2DD6 Kleinfelder, Inc. KLEJNFELDER conform to Section 9-03.14(1) Gravel Borrow of the WSDOT Standard Specifications. Structural fill placed behind retaining walls or below grade structures not designed to withstand hydrostatic pressures should consist of free -draining sand and gravel conforming to the requirements of Section 9-03.12(2) Gravel Backfill for Walls of the WSDOT Standard Specifications. The on-site soils are not suitable for reuse as structural fill. Therefore, the contract documents should include unit costs for both export of on-site soil and import of fill that meets the recommendations presented in the previous paragraph. The contractor should submit samples of each of the required earthwork materials to the geotechnical engineer for evaluation and approval prior to use. The samples should be submitted at least 4 days prior to their use and sufficiently in advance of the work to allow the contractor to identify alternative sources if the material proves unsatisfactory. Prior to placement, structural fill should be moisture conditioned to within 3. percent of the optimum moisture content. All structural fill should be compacted to the following minimum relative compaction based on ASTM D1557 Modified Proctor compaction test methods: Structure Subgrades (including Temporary Work Pad): 95 Percent Pavement Subgrades: 95 Percent (upper 2 feet) Pavement Subgrades: 90 Percent (below 2 feet) Utility Trenches: 95 Percent (upper 2 feet) Utility Trenches: 90 Percent (below 2 feet) 3.2.4 Temporary excavations General All excavations, including slopes, must comply with applicable local, state, and federal safety regulations including the current OSHA Excavation and Trench Safety Standards and WSHA Safety Standards for Construction. Such regulations are strictly enforced and, if they are not followed, the owner, contractor, and/or earthwork and utility subcontractors could be liable for substantial penalties. Construction site safety is the sole responsibility of the contractor, who shall also be solely responsible for the means, methods, and sequencing of construction operations. We are providing the information below solely as a service to our client for preliminary planning purposes. Under no 64923/sEA6R059.doc Page 11 of 18 March 1D, 2006 Copyright 20D5 Kleinfelder, Inc. NO KLFIINF£LDFR circumstances should the information be interpreted to mean that Kleinfelder is assuming responsibility for construction site safety or the contractor's activities; such responsibility is not being implied and should not be inferred. The existing soils are relatively weak, and should be sloped no steeper the 2.1 H:V for temporary slopes and cuts. The maximum anticipated vertical height for a temporary slope at this project site is 10 feet. Shallower and/or less steep slopes may be necessary for temporary excavations below the groundwater table. Alternatively, for temporary slopes higher and/or steep then recommended previously, shoring can be designed to support temporary slopes. Construction Considerations Heavy construction equipment, building materials, excavated soil, and vehicular traffic should not be allowed within one-third the slope height from the top of any excavation. Where the stability of adjoining buildings, walls, or other structures .is endangered by excavation operations, support systems such as shoring, bracing, or underpinning may be required to provide structural stability and to protect personnel working within the excavation. Earth retention, bracing, or underpinning required for the project (if any) should be designed by a professional engineer registered in the State of Washington. Slope Protection Temporary slopes should be protected from the elements by covering with a protective membrane consisting of plastic sheeting or some other similar impermeable material. Sheeting sections should overlap by at least 12 inches and be tightly secured with sandbags, tires, staking, or other means to prevent wind from exposing the soils under the sheeting. Permanent slopes should be planted with a deep-rooted, rapid -growth vegetative cover as soon as possible after completion of slope construction. Alternatively, the slope should be covered with plastic, straw, etc. until it can be landscaped. 3.2.5 Weather Considerations During periods of wet weather, the contractor should take measures to protect on-site excavations and subgrade once the geotechnical engineer has approved them. These measures could include, but are not limited to, placing a layer of crushed rock or lean concrete on the exposed subgrade, or covering the exposed subgrade with a plastic 648231SEABR059.doc Page 12 of 18 March 10, 2006 Copyright 2006 Kleinfelder, Inc. k" K L E I N F F L D E R tent. If additional overexcavation is required because the subgrade was not protected, the cost of such additional work should be borne by the contractor. The on-site soils are moisture sensitive and will be easily disturbed when traversed by construction equipment during wet weather. After a rainfall, construction equipment travel on the exposed site subgrade should be minimized until the soils have been allowed to dry sufficiently. During wet weather, earthen berms or other methods should be used to prevent runoff water from entering all excavations. All runoff water should be collected and disposed of outside the construction limits. 3.3 FOUNDATIONS Based on the site conditions encountered and our understanding of the proposed development, it is our opinion that the proposed building should be founded on a deep foundation system, such as auger -cast piles, or an intermediate foundation system such as Geopierso. Design of a pile foundation or Geopier` system is. not within our current scope services. However, once building loads have been finalized, Kleinfelder can assist in the design of an auger -case pile foundation system and/or parameters for design of a Geopier® system by Geopier Foundation Company. For preliminary planning purposes, we anticipate that 18 -inch diameter auger -cast concrete piles would require about 10 to 15 feet of embedment into the dense older alluvium to achieve allowable capacities on the order of 75 kips. Geopiers® can be a cost-effective, "intermediate" foundation alternative when a suitable foundation subgrade can be located within approximately 20 to 30 feet of the ground surface. However, the shallow groundwater at the site may limit the usability and/or cost-effectiveness of Geopiers° as a foundation alternative. Kleinfelder can assist you in discussions with local Geopier` companies, such as Northwest Geopier', if desired. Typically, shallow foundations and concrete slab -on -grade floors are designed for a structure and the Geopier system is then designed on a project -specific basis to support those shallow foundations. The following recommendations are provided for design of shallow foundations founded directly on Geopiers and are not suitable for other applications at this site. 64923/SEA6RD59.doc Page 13 of 18 March 10, 2406 Copyright 2006 Kleinfelder, Inc. f`■ KLEINFELDER Minimum Footing Width Isolated Column Footings: 24 inches Continuous Strip Footings: 18 inches • Preliminary Allowable Soil Bearing Pressure for Footings Founded Directly on Geopiers®: 2,500 psf Note: Allowable soil bearing pressures are for all dead and live loads and may be increased by one-third far temporary short-term wind and seismic loads. A final allowable soil bearing pressure should be reviewed and confirmed by Kleinfelder based on the foundation Geopiers® designs. Lateral Load Resistance Allowable Passive Resistance.- Existing esistance: Existing Soils Above the Groundwater Table: 160 pcf EFW Compacted Structural Fill: 260 pcf EFW Allowable Coefficient of Friction for Sliding Resistance: Concrete cast on Geopiers® or Structural Fill. 0.35 Note: The allowable passive pressure includes a safety factor of about 2. Mobilization of this passive pressure requires significant structural deflection and Kleinfelder should be consulted before utilizing this pressure in design. The upper foot of soil should be neglected in design computations unless protected by pavement or a slab -on -grade. The allowable coefficient of friction includes a safety factor of 1.5. Static settlement will be dictated by Geopier® design but is typically as follows: Total Settlement: less than 1 inch Differential Settlement: less than 314 an inch over 50 feet Time Rate: approximately 90 percent during construction Buoy Considerations: It should be noted that portions and/or all of the proposed building subgrade structures may be located below the groundwater level at the project site for all or part of the year, based on the shallow groundwater levels observed at the project site. Building foundations should be selected and designed to resist buoyant forces acting on the 649231SEA6R059.doc Page 14 of 78 March 10, 2006 Copyright 2006 Kleinfelder. Inc. k" KL EINFFLDER building. Furthermore, subgrade walls should be designed for long-term hydrostatic forces. Kleinfelder should be consulted to provide additional recommendations once the location and depth of below -grade structures are determined. 3.4 FLOOR SLABS Floor slabs for the proposed building should be supported on either auger -cast concrete piles or Geopiers® and be designed as a structural slab. We recommend perimeter subgrade drains be installed along the building to reduce the potential for water intrusion beneath the at -grade floors. In addition, the floor slabs should be underlain by a minimum 4 -inch thickness of sand and gravel that meets the requirements Section 9-03.9(3), Base Course, of the WSDOT Standard Specifications. In areas where moisture would be detrimental to equipment, floor coverings or furnishings inside the building, a vapor barrier should be placed beneath the concrete floor slab. A 10 -mil thick plastic sheeting overlapped at least 12 inches at the seams is satisfactory for this purpose. If desired, a layer of sand, approximately 2 inches thick, may be placed over the plastic sheeting to protect it from damage and to act as an aid in curing of the concrete slab. Care must be taken to prevent the sand from becoming saturated prior to placing concrete. 3.5 SEISMIC DESIGN The following seismic design criteria should be used for the design of structures constructed at the project site. In accordance with Section 1615 of the 2003 IBC and based on the results of the standard penetration tests performed at the site, a Site Class of D is appropriate. The following general -procedure design spectral response acceleration parameters should be used: Table 9 -- IBC 2003 Design Coefficients er �' Y �`�. � NV � //���� Int!!t ry, 11n4 _Si L�Q � � � T �Si .Sp�fra •:s iY. f l t R�laf.T� �''`,} f. i -`i+•1 _� :{��' Y 'fiY Y .d ?' '^ii' C 4 rix �} n,p� i ,u f`p,_•,{R,�3' 4 F1 �, .p2^ � 4� 'JZ'iK�� � }�'. Z � i CS � 4 -Fj C �� F i� - ^,,� k.'��E -�'i� � � a.� �.�2n� y�', 4G�w ^n k 1.35 0.46 1.0 1. 55L 0.90 0.48 0.11 0.53 0.36 �.I yk I kW — DS.J 64923/SEA6R059.doc Page 15 of is March 16, 2006 Copyright 2006 Kiainfeider, Inc. K L F IN F E L DER The loose, saturated sandy soils located at the site are susceptible to earthquake - induced liquefaction. However, in our opinion, supporting the proposed structure and slabs on auger -cast concrete piles or Geopierso that bear in the dense older alluvium will mitigate liquefaction hazards for the building. Liquefaction may result in limited differential settlement in the parking lot and areas surrounding the structure. We have not performed a quantitative liquefaction analysis for this site to estimate the extent of liquefaction or liquefaction -induced settlement. 3.6 LATERAL EARTH PRESSURES Lateral earth pressures for use in designing earth retention and below -grade structures are provided below. The lateral earth pressures provided herein assume all backfill will consist of imported and properly compacted free -draining structural fill material as discussed in Section 3.2.3. If temporary shoring is required to support excavations, Kleinfelder can provide case -specific design recommendations. Wall free to rotate at top (assuming no hydrostatic pressure): Compacted Structural Fill: 35 pcf EFW Wall fixed at top (assuming no hydrostatic pressure): Compacted Structural Fill.• 50 pcf EFW Horizontal Traffic surcharge (where applicable): 75 psf applied over upper 10 feet Fixed wall below groundwater level: Compacted Structural Fill: 95 pcf EFW Note: These values do NOT include lateral loads due to floor, seismic, or other vertical loads. Any such loads should be added to the above soil pressures for design. 3.7 DEWATERING AND DRAINAGE 3.7.1 Dewatering Based on groundwater conditions observed during our exploration, we anticipate that dewatering will be required during construction of subgrade structures below the groundwater table, and may be necessary for the successful construction of Geoplerso. A dewatering study and design, including anticipated quantities and flow rates, pump design, and discharge parameters and recommendations should be performed for this 649231SEA6RO59.doc Page 15 of 1$ March 10, 2006 copyright 2006 Klainfelder, Inc. KLEINFELDER site once the anticipated site grades and structure depths are finalized, Kleinfelder has not installed any groundwater monitoring wells at this project site at the time of this report. However, we recommend that such wells be installed to assist in developing a dewatering study and design It should be noted that the proposed below -grade structures may be submerged for part or all of the year, based on the shallow groundwater levels observed during our field exploration. The below -grade structures for the proposed building should be designed to be waterproof and account for hydrostatic forces. Alternatively, permanent dewatering measures could be implemented at the site to maintain the groundwater level below the lowest grade of the building. However, in our experience this is costly and rarely practical. 3. %2 Drainage During construction, surface drainage not associated with the shallow groundwater table can be controlled by careful excavation practices. Typically, these include, but are not limited to, shallow upgrade perimeter ditches or low earthen berms, and temporary sumps in excavations to collect seepage and prevent water from damaging exposed subgrades. Drains should be included at the bottom of all temporary slopes to collect surface water flow from the slope and prevent it from flowing onto exposed building or pavement subgrades. All collected water should be conveyed under control to a positive and permanent discharge system, such as a storm sewer. Recommendations for permanent footing drains are provided in Section 3.3.- All permanent drains should convey water under control to a positive and permanent discharge point well away from the structure. Roof downspouts should not be connected to footing drains, but should be tight lined separately to a positive discharge system. This will avoid the potential for roof debris to be washed into footing drains, possibly blocking them. Clean -outs should be provided for footing drains and the downspout tight lines. Drains should be backfilled with clean, free -draining gravel or crushed rock meeting the requirements of Section 9-03.12(4), Gravel Backfill for Drains, of the WSDOT Standard Specifications. 649231SEA6R059.doc Page 17 of 18 March 10, 2006 Copyright 2006 Kleinfelder, Inc. KL E I N F F L D E R 3.8 UTILITIES The contractor should be responsible for the safety of personnel working in utility trenches. Dewatering will be required for utility trenches that extend below the groundwater level. We recommend all utility trenches, but particularly those greater than- 4 feet in depth, be supported in accordance with state and federal safety regulations. Structural fill should be placed and compacted as described in Section 3.2.3. Particular care should be taken to make sure bedding or fill material is properly compacted in place to provide adequate support to the pipe. Jetting or flooding is not a substitute for mechanical compaction and should not be allowed. 4.0 ADDITIONAL SERVICES The recommendations made in this report are based on the assumption that an adequate program of tests and observations will be made during construction to verify compliance with these recommendations. Testing and observations performed during construction should include, but not necessarily be limited to, the following.- • Observations and testing during site preparation, earthwork, structural fill, and pavement section placement, • Testing and inspection of concrete, masonry, structural steel, fireproofing, and roofing materials. • Consultation as may be required during construction. We further recommend that project plans and specifications be reviewed by us to verify compatibility with our conclusions and recommendations. Also, Kleinfelder maintains fully accredited, WABO-certified laboratory and inspection personnel, and are available for this project's testing and inspection needs. Information concerning the scope and cost for these services can be obtained from our office. 64923fS1=A5RD59.doc Page 18 of 18 March 10, 2006 Copyright 2006 Kleinfelder, Inc_ Archaeological Sampling of Property at 621 SW Grady Way, Renton, Washington DRAFT REPORT David T. Francis, Ph.D. and David V. Ellis, M.P.A. November 3, 2008 Prepared for the Washington State Auto Dealers Association Seattle, Washington Willamette Cultural Resources Associates, Ltd. Portland, Oregon WillametteCRA Report 08-13 Introduction The Washington State Auto Dealers Association (WSADA) is considering purchase of a property at 621 SW Grady Way in Renton, Washington. To assist the WSADA in this decision, an assessment of the potential for archaeological resources on the property was conducted by Historical Research Associates, Inc. (HRA). HRA reviewed the literature on previous archaeological studies in the Renton area and other information. Based on their research, HRA concluded that the property had a high potential for archaeological resources and recommended that subsurface probes be excavated across the property to determine if such resources are present (Kaehler and Thompson 2008). The WSADA recently decided to proceed with implementing the HRA recommendations and has contracted with Willamette Cultural Resources Associates, Ltd. (WillametteCRA) to undertake subsurface exploratory excavations on the property. In addition to the field investigations, Willamette CRA has reviewed records of the Washington Department of Archaeology and Historic Preservation (DAHP) to update the research conducted by HRA. WillamctteCRA has also undertaken coordination with four Indian Tribes on behalf of the WSADA regarding the proposed excavations. WillametteCRA completed the archaeological sampling at the Renton property on October 27, 2008. This report provides the results of the sampling, which can be quickly summarized as not identifying any prehistoric or historic archaeological remains older than 50 years. Further details of environmental and cultural history help illuminate the significance of these results. In addition, a narrative review of the project background helps clarify the process by which properties like the property of interest to the WSADA came to be developed. A third and fourth section provide a thorough account of the methods and results that enabled WillametteCRA to make this determination, as well as recommendations and references. Environmental and Cultural History As part of their work to assess the potential of archaeological resources on the property, HRA provided a detailed overview of both environmental and cultural context. The brief treatment of these topics that follows below is intended to re -familiarize readers with only the most salient features of the overview. The Renton area was buried under several thousand feet of ice of the Puget Lobe of Cordilleran ice between about 15,000 and 12,000 years ago (http://www.egy.wa.gov/programsZsea/"12ugetsound/tour/geology.html). Glacial meltwaters formed massive lakes and helped accumulate thick beds of sediment that are still very much in evidence at the property. Runoff from mountain streams also played a dynamic role in the project neighborhood, as both the Black and Cedar rivers funrncled into the Renton valley, their courses often changing over time. The floodplain between these competing rivers probably stabilized enough to provide an occupation surface by about 2,500 years ago (Kaehler and Thompson 2008:3). Although prehistoric populations existed in the Puget Sound area soon after the retreat of the glaciers, the surrounding high-energy landscape of postglacial meltwater and flood deposit, has made detection of such ancient cultures highly problematic. 'Tellingly enough, all of the eight sites that Historical Research Associates (HRA) identified within 2.0 miles from the site, are fairly recent, dating between 200 — 500 years ago (Lewarch 2004:3) based on stratigraphy. In their 2008 report, HRA speculated that the area "was probably available for prehistoric Native American groups between 2,500 and 2,000 years ago" (Kaheler and Thompson 2008:13) by the same tribe (the Duwamish) that lived in the area when Euroamericans first began filing land claims along the Black and Cedar river corridor. For the 8,000 years prior to that time when people lived in western Washington, the property area was probably not accessible for occupation due to drainage patterns or swamp - like conditions that would have discouraged settlement. The Duwamish relied on salmon runs along these rivers, living in a series of villages located close to traditional fishing grounds. Moreover, edible plant foods such as camas and wapato, which favor wet environments similar to floodplains, contributed substantially to native diets. Historic development of the Renton area (first platted in 1875) occurred in tandem with the discovery of coal beds at the south end of Lake Washington as early as 1853 (http://www.burgesslegacy.org/coalhst.htm). As HRA's report mentions, the property on Southwest Grady Way was not part of the city of Renton until the mid -twentieth century (Kaehler and Thompson 2008:6). The property itself (Figure 1 — photo of site) measures approximately half an acre, characterized by a fairly flat landform with minor dips and mounds caused by previous disturbance. It is wooded primarily with mature bigleaf maple (Acer macmphyllum), along with occasional alder (Alnus sp.), cottonwood (Populus sp.), English holly (Ilex aquifolium), and spurge laurel (Daphne laureola). Understory shrubs include natives such as swordfern (Pojhstichum munitum) and sal -al (Gaulthena shallon), as well as invasive blackberries (Ruhus sp.) and Scotch broom (Cytisus scoparaus), particularly on the western edge. Project Background The undeveloped, half acre project site on has been available for purchase and development for the past several years (Figure 2). The environmental firm Kleinfelder first performed geotechnical evaluation of the property for the Pharr Company, which had proposed the construction of an automotive body shop. When, in late 2007/early 2008, the WSADA expressed interest in acquiring the property for construction of a multi-level conference center, it contracted with Kleinfelder (through The Robinson Company) to re- evaluate the site with the specific development needs of the WSADA. The HRA study referenced above was undertaken following the geotechnical studies and incorporated the results of geotechnical excavations. The WillametteCRA sampling on October 27 consisted of excavation of a series mechanical auger probes and a backhoe pit at the direction of WillametteCRA staff archaeologist David Francis, Ph.D. Rather than repeat the research work completed by HRA in terms of the site's environment, ethnography, and history, this report focuses more narrowly on the sampling, further details of which are provided below ("Methods and Results" section). While the bulk of WCRA's work consisted of examining the sediments from the subsurface explorations, Dr. Francis also reviewed DAHP records to determine if any new data regarding cultural resources in the area had been submitted to the DAHP in the eight months since HRA's report of February 2008. Methods and Results Updated Records Review Prior to the sampling work on October 27, WillametteCRA conducted an updated records review at DAHP in Olympia on October 14. Previous review of DAHP records by HRA indicated that 16 archaeological studies over the past 30 years focused on the floodplain of the Black and Cedar rivers, the same general landform as the property occupies. These studies had identified eight prehistoric and historic sites within two miles of the present project location. Updated research conducted by WillametteCRA revealed that a single additional study had recently been completed in the vicinity (Hoyt et al. 2008), which had not identified any no new archaeological resources within two miles of the property. WillametteCRA also identified several additional (previously undertaken) archaeological studies in the area (Shong and Miss 2004; Smith and Hoffman 2007) that had also not resulted in any new sites. Archaeological Sampling In order to obtain a representative sample of the property's subsurface deposits as fully as possible, WCRA determined that eight mechanical auger probes (MAs) should be excavated across the property (Figure 3). Since several of the previously identified sites in the vicinity (Tualdad Altu, 45KI59 and the Renton Sears Fred Meyer Store site, 45KI439) concealed deeply buried deposits up to 3 meters (m) (9.8 feet [ft]) beneath the surface (Kaehler and Thompson 2008:11), our NIAs were excavated to depths of 3.7-4.6 in (12-15 £t). As mentioned at the outset of this report, no cultural resources older than 50 years were observed in any of the bore holes. A single ceramic fragment, with a blue-green glaze and floral pattern, possibly from a cup or bowl, appeared in the first 50 centimeters (cm) (20 inches [in] D of MA -1. This fragment is consistent with other modern debris on the surface of the site and was not interpreted as historic. Fragments of clear glass, both bottle and probable window glass, occurred as deep as 1.5 m (5 ft) in NLA, -2, associated with the fill that characterized MA -2. While the dense blackberry underbrush on the property must have been cleared to enable geotechnical evaluation in 2006, significant re -growth prevented easy access. Kevin Waller of Northwest Excavating cleared a path for the drill rig, operated by Codey Fernandez and Kevin Rogers of Gregory Drilling. Removal of one or two smaller trees enabled the drill rig to access pockets in the southwest corner of the property. The extreme 3 southeast corner, densely crowded by trees and overgrown logs, could not be accessed. All other areas of the site accommodated the drilling equipment. Once the brush had been cleared, Dr. Francis inspected the surface, noting abundant cobbles among the humus and leaves, as well as modern refuse around the edges and especially along the west side of the property where the shoulder of Raymond Avenue offers parking. A pile of concrete foundation blocks (Figure 4), possibly the remains of a cistern or trough, forms a mound in the central western portion of the property, although no buildings have been known to exist on the property (Kaehler and Thompson 2008:8,13). It is likely that this material was introduced or dumped on the property as a convenient means of disposal. With a diameter of 16 cm (6'/4 in), the auger created a hole measuring approximately 30 cm (12 in) in diameter. Soil would quickly mound up around the perimeter of the bare. In order to sample sediments without slowing the progress, Mr. Rogers shoveled off the spoils that the rotating auger continually brought to the surface over to Dr. Francis, who inspected the soil and recorded notes approximately every 50 cm (18-24 in). The location of each MA was recorded with GPS and photographed. GPS data for the eight NLAs is as follows: Bore Hole# 10T UTM Elev. MA -1 0558324 5257380 3m MA -2 0558331 5257363 13m MA -3 0558401 5257388 12m MA -4 0558392 5257386 8m MA -5 0558369 5257390 15m 14L,k-6 0558362 5257378 1 Um hL),-7 0558349 5257374 5m MN A-8 0558337 5257375 Sm To better view the stratigtaphy of the site down to a depth of 3.7 m (12 ft), Dr. Francis directed Mr. Waller to open a west -cast trench of approximately 3.7 m in length and 0.9 m (3 ft) in width along the central northern edge of the property. 11t a depth of 1.8 in (6 ft), Dr. Francis cleaned the west wall of the trench and photographed three primary strata below the topsoil (Figure 5): a light brown silty -sand with 20% gravels and occasional fist - sized cobbles (stratum 1) extending to a depth of 09 m (3 ft); a medium brown silty -sand with 10% gravels and no cobbles (stratum 2) extending to a maximum depth of almost 1.8 m, and a grey -blue silty clay without gravels or cobbles (stratum 3) sloping to the south to a minimum depth of 1.5 m (5 ft) and maximum depth of 1.8 m in the north. The grey -blue clay bears a strong resemblance to Lawton clay, the dark blue -grey clay and silt that many Northwest geologists attribute to accumulation in a massive freshwater lake created by glacial meltwatcrs (see http://www.ecy.wa.gov/programs/_ sea /pugetsound/tour /geologyT.html). The gravelly sands above the clay likewise bear a striking resemblance to what is termed in local geological parlance Esperance Sand, a loose, yellow sand desposited by glacial meltwater and mountain stream run-off. The boundary between the sand and the clay, is clearly visible in the west wall profile of the trench. 4 Mr. Waller continued excavating the trench down another 1.8 in (6 ft), bringing the bucket up to the surface for macro -photographs of stratum 3, which below 1.8 m graded into agrey silty clay mottled with red clays. The trench was then backfilled. While minor differences occurred between the eight MAs, the three basic strata observed in the trench were also typically present across the property. All three strata correspond to what Ward and Hyllseth (2008:3) interpreted as "younger alluvium" typical of low energy environments. Below the topsoil, a layer of light brown silty -sand with 20% rounded gravels, rootlets, and occasional fist -sized cobbles extended to a depth of about 2.4- 3.0 rn (8-10 feet), when an increase in clay content could be detected by a sudden "balling" of sediments into small pebble -sized clumps by a depth of 3.7 m (12 ft). Below this depth, gravels and cobbles were absent and the "balling" increased in size to become fist -sized by about 4.0 m (13 feet). Moments after the appearance of larger clumps of medium brown silty clay loam, the auger would bring up a distinctive grey -blue silty clay, often wet to the touch (Figure 6). This grey -blue silty clay is probably the same "deltaic mud" that has been abundantly documented throughout the Green and Duwamish valleys (see, for example, Shong and Miss 2004:3). Holes were terminated at this stratum and backfilled with bentonite. Six of the eight MAs reached depths of 4.6 m (15 ft) below the surface. Two others, MA -1 and MA -2, in the western portion of the site, were terminated at 3.7-4.0 m (12-13 ft) in recognition of the fact that alluvial sands are much deeper in the western portion of the site, as established by former geotechnical analysis. Indeed, in these two MAS, the grey -blue clay was not detected on even the tip of the drill teeth at 4.0 m below the surface. It should be noted that the relatively shallow depth of the archaeological borings did not at any time reach the 9-12 m (30-40 ft) range that many of the geotechnical borings did, and that the "older alluvium" observed by Ward and Hyllseth below depths of 6.1 m (20 ft) was not in evidence. Based on the 2008 geotechnical report, WillametteCRr1 staff had an expectation that native soils lay deeply buried on the property, possibly as much as 1.5 m (5 ft) beneath fill consisting of sand, gravel, and construction debris. With the single possible exception of NL,k-2, WCRA did not observe fill to extend below 0.75 m (2.5 ft) at any point across the site. Particles of sheetrock or drywall, as well as blacktop macadam and clear glass fragments, appeared in the soil as deep as 1.5 m in MA -2, but because the surface area surrounding the top of this MA was densely littered with the same material, it seems just as likely that such debris was falling in from the sidewall or otherwise contaminating the sample and that the fill did not extend as deeply as it might appear. While Kleinfelder's report (2008, Appendix A -3b and A-6) indicates that the depth of fill in hole B-2 extended to about 1.5 m (5 feet), the immediately adjacent TP -3 shows fill extending only 35 cm (14 in) below the surface. Since MA -1 was also placed in the same area in the northwest corner of the property, it would have been reasonable to expect to see fill material similar to the Kleinfelder's B-2 or TP -3, yet the light brown silty sands with 20% gravels that occurred in MA -1 from beneath the topsoil down to more than 2 m (6 ft) did not contain any of the modern debris characteristic of fill.. k Dr. Francis observed that the ground surface lies below street level at least 1 m (3.3 ft) on both sides of Southwest Grady Way. This difference in elevation suggests that perhaps the upper portion of the soil on the ptopetty had been pushed north to create a berm or raised platform for the road, possibly in the 1920s when a Metsker Map first records a spur of the Columbia and Puget Sound Railroad about half a mile north (Kaehler and Thompson 2008:8). With these observations taken into consideration, along with the direct evidence offered by the M As, it would seem most likely that the light brown gravelly sands across the site are NOT fill, but more consistent with floodplain deposits of the Black and Cedar rivers. Fill is more commonly associated in the area with the continuous presence of artificial materials in the sediment such as asphalt (see, for example, Smith and Hoffman 2007:4). As Kaehler and Thompson (2008:3) emphasize in their reading of Kleinfelder's work, the absence of fill along the southern boundary is noteworthy due to flood deposits occurring immediately beneath the topsoil. In Dr. Francis' interpretation, this is in fact true for much of the site, not just the southern boundary. KleinfeIder's Ward and Hyllseth (2008:3) also observed that during the winter of 2006, when they conducted the geotechnical evaluation, "groundwater was generally encountered... at depths ranging between 6 and 9 feet below ground surface." During WCRA's investigation, groundwater was not detected until 4-5 in (13-16 ft), consistent with Kleinfelder's hypothesis that seasonal fluctuation of groundwater could be anticipated. To be precise, WillametteCRA interpreted the presence of groundwater as a very wet blue -grey clay that fell or ran freely off the drill bit. Tribal Coordination WillametteCRA sent certified letters on October 13, 2008, to the cultural resource contacts with the Duwatnish, Muckleshoot, Puyallup, and Suquamish Tribes informing the Tribes of the proposed field investigations and inviting Tribal representatives to be present. We also requested any information or concerns the Tribes might have regarding the location. Postal Service receipts indicated all four letters were delivered. The letters were followed up with telephone calls and emails informing the Tribes of the scheduled fieldwork and reiterating the invitation for Tribal representatives to be present. None of the Tribes responded to these communications. Copies of this report will be provided to all four Tribes. Recommendations The WillametteCRA field investigation observed no evidence of archaeological or historical resources on the surface or in the subsurface samples. None of our observations indicated that archaeological or historical resources are likely to be present. It is therefore our professional opinion that development on the property is unlikely to encounter any archaeological or historical resources. No further archaeological studies are therefore recommended. Should evidence of archaeological resources be encountered during construction that may be undertaken by the WSADA, all ground -disturbing activity should cease immediately in the vicinity of the discovery and the DAHP and Tribes promptly notified. Further ground -disturbing activity should not resume until approved by the DAHP and Tribes. 2 Should evidence of human remains be encountered, all ground -disturbing activity should cease immediately in the vicinity of the discovery and the City of Renton Police Depattment, the King County Coroner, DAHP, and the Tribes promptly notified to ensure compliance with RCW 27.44.055 and RCW 68.60.055. Further ground -disturbing activity should not resume until approved by the appropriate agencies and Tribes. References Hoyt, Bryan, James B. Harrison III, and Paula Johnson 2008 Cultural Resources .survey of the CedarRapids Floodplain Restoration Project, Kang County, Washington. Submitted to King County Water and Land Resources Division, Seattle. Kaehlet, Gretchen and Gail Thompson 2008 Potential forArchaeological Resources at the IFSADA Parcel on SIS Gray [sic] Vay, City of Renton, King County, Washington. is Research Associates, Inc. Submitted to The Robinson Company, Seattle, Washington. Lewarch, Dennis E. 2004 Dexudideav, the 11ttle Cedar Raver .Fishing Site. Site inventory form on file at the Washington Department of Archaeology and Historic Preservation, Olympia, Washington. Shong, Michael, and Christian Miss 2004 Cultural Resource Monitoring for the South Treatment Plant Cogeneration Facility, City of Renton, King County, Washington. Northwest Archaeological Associates Inc., Seattle. Prepared for King County Department of Natural Resources and Parks, Seattle.. Smith, Craig S., and Robin Hoffman 2007 Cultural Resource Inventory of the Columbia Bang Parcel, King County, Washington. Entrix, Inc. Seattle. Prepared for Zenczak & Partners, Architects, Tacoma, Washington. Ward, Scott, and Rolf Hyllseth 2008 Preliminary Geotechnical Evaluation, Proposed Development, 621 South Grady Way, Renton, Washington. Kleinfelder West, Inc.. Submitted to Washington State Auto Dealers Association, Seattle. Washington State Department of Ecology, Puget Sound Shorelines (website) 2008 ht www.e .wa. ov ro s sea a etsound tour eolo .html 7 dAL tan ^t ^1 O. 1. leiJL �. sell ~J k [s ;a� Park , I � of �1% j duck f? ue•4 f V ; y.� ii 3 i r� I., �rcpiaq 51a ar� WSADA Property _ I op . wx r = 46 JO ;t U s.•s r R'A Tukwila. '_ 11� Base map from Renton. WA 1994, USGS ` 7.5 -minute topographic quadrangle. !" 0 180 360 720 1,090 1,44UMeters N Figure 1. WSADA project location. Figure 2. Northern portion of the project property, looking east along SW Grady Way from Raymond Avenue SW. t Gly Suutnwg5 ��T-}}rench o a LD 01 8 4 0 0 07 0 02 5 41 WSAOA Property g 1 ❑ 60 Feet N 0 20 Meters 03 Mechanical Auger Figure 3. Location of archaeological exploratory subsurface probes at the project site. E Figure 4. Concrete debris in the western portion of the project site. 10 Figure 5. West wall of the backhoe trench indicating the three strata identified in the trench. ll Figure 6. Typical exposure of blue -gray silty clay during augering. 12 APPENDIX J Operation and Maintenance Manual 19 Maintenance Plan Goal The Washington State Auto Dealers Association will be responsible for the maintenance and operation of the stormwater facilities located on the Washington State Auto Dealers Association project site. The objective of the following plan is to provide the owner a manual for maintaining the on-site stormwater management facilities. The attached checklists will be used in maintaining the facilities. Introduction/System Overview The site stormwater management facilities include a stormwater conveyance system, detention facility, conveyance swales, and a StormFiLter(D treatment facility. The underground StormTech facility is intended to provide stormwater flow control. The StormFilter(D cartridges will provide stormwater treatment. The on-site storm system requires regular maintenance. The stormwater conveyance system must be inspected after Large storm events. Leaves and debris shall be swept clean of the catch basins The Operations and Maintenance Manual must be kept where it can be accessed by the Washington State Department of Ecology, City of Renton or any other agency with jurisdiction over the stormwater system. The attached checklists indicate maintenance actions which must be performed to keep the system in proper operating condition. Inspection Frequency and Record Keeping Inspection should be completed a minimum of two (2) times every year and records of inspection and maintenance must be kept for five (5) years. A copy of the maintenance plan/checklist should remain on site. 20 Pollution Source Control The applicant/owner shaLL be responsible for controlling potential pollutants at their point of use or generation. Pollution source control is the application of pollution prevention practices to prevent contamination of stormwater runoff. The plan of action will include elements such as a centralized area for the storage of equipment, lubricants, pesticides, and other potential pollutants. The owner may elect to follow the detailed guidance on control of sediment pollutants as outlined in the King County Surface Water Design Manual. The most important practice is to ensure that no hazardous wastes, such as oil, will be dumped into the storm drainage system. Maintenance Schedule Refer to the attached "Instructions for Use of Maintenance Checklists", following Attachment 'A' of this report. 21 Attachment "A" Maintenance Program Cover Sheet Inspection Period: Number of Sheets Attached: Date Inspected: Name of Inspector: Inspector's Signature: 22 Instructions for Use of Maintenance Checklists The following pages contain maintenance needs for most of the components that are part of your drainage system, as well as for some components that you may not have. Let the City of Renton know if there are any components that are missing from these pages. Ignore the requirements that do not apply to your system. You should plan to complete a checklist for all system components on the following schedule: 1. Monthly from November through April. 2. Once in late summer (preferably September) 3. After any major storm (use 1 -inch in 24 hours as a guideline) Using photocopies of these pages check off the problems you looked for each time you did an inspection. Add comments on problems found and actions taken. Keep these "checked" sheets in your files, as they will be used to write your annual report. Some items do not need to be looked at every time an inspection is done. Use the suggested frequency at the left of each item as a guideline for your inspection. 23 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.4 - CONTROL STRUCTURE/FLOW RESTRICTOR Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed Structure Trash and debris Trash or debris of more than '/� cubic foot which No Trash or debris blocking or is located immediately in front of the structure potentially blocking entrance to opening or is blocking capacity of the structure by structure. more than 10%. Trash or debris in the structure that exceeds '13 No trash or debris in the structure. the depth from the bottom of basin to invert the lowest pipe into or out of the basin. Deposits of garbage exceeding 1 cubic foot in No condition present which would volume. attract or support the breeding of insects or rodents. Sediment Sediment exceeds 60% of the depth from the Sump of structure contains no bottom of the structure to the invert of the lowest sediment. pipe into or out of the structure or the bottom of the FROP-T section or is within 6 inches of the invert of the lowest pipe into or out of the structure or the bottom of the FROP-T section. Damage to frame Corner of frame extends more than'/4 inch past Frame is even with curb. andlor top slab curb face into the street (If applicable). Top slab has holes larger than 2 square inches or Top slab is free of holes and cracks. cracks wider than 'A inch, Frame not sitting flush on top slab, i.e., Frame is sitting flush on top slab. separation of more than 1% inch of the frame from the top slab. Cracks in walls or Cracks wider than 1/2 inch and longer than 3 feet, Structure is sealed and structurally bottom any evidence of soil particles entering structure sound. through cracks, or maintenance person judges that structure is unsound. Cracks wider than X. inch and longer than 1 foot No cracks more than '14 inch wide at at the joint of any inlet/outlet pipe or any evidence the joint of inlet/outlet pipe. of soil particles entering structure through cracks. Settlement/ Structure has settled more than 1 inch or has Basin replaced or repaired to design misalignment rotated more than 2 inches out of alignment. standards. Damaged pipe joints Cracks wider than '/,inch at the joint of the No cracks more than '/a -inch wide at inlet/outlet pipes or any evidence of soil entering the joint of inlet/outlet pipes. the structure at the joint of the inlet/outlet pipes. Contaminants and Any evidence of contaminants or pollution such Materials removed and disposed of pollution as oil, gasoline, concrete slurries or paint. according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Ladder rungs missing Ladder is unsafe due to missing rungs, Ladder meets design standards and or unsafe misalignment, rust, cracks, or sharp edges. allows maintenance person safe access. FROP-T Section Damage T section is not securely attached to structure T section securely attached to wall wall and outlet pipe structure should support at and outlet pipe. least 1,000 lbs of up or down pressure. Structure is not in upright position (allow up to Structure in correct position. 10% from plumb). Connections to outlet pipe are not watertight or Connections to outlet pipe are water show signs of deteriorated grout. tight; structure repaired or replaced and works as designed. Any holes—other than designed holes—in the Structure has no holes other than structure. designed holes. Cleanout Gate Damaged or missing Cleanout gate is missing. Replace cleanout gate. 2009 Surface Water Design Manual – Appendix A 1/9/2009 A-7 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.4 - CONTROL STRUCTURE/FLOW RESTRICTOR Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed Cleanout gate is not watertight. Gate is watertight and works as designed. Gate cannot be moved up and down by one Gate moves up and down easily and maintenance person. is watertight. Chainlrod leading to gate is missing or damaged. Chain is in place and works as designed. Orifice Plate Damaged or missing Control device is not working properly due to Plate is in place and works as missing, out of place, or bent orifice plate. designed. Obstructions Any trash, debris, sediment, or vegetation Plate is free of all obstructions and blocking the plate. works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all obstructions and potential of blocking) the overflow pipe. works as designed. Deformed or damaged Lip of overflow pipe is bent or deformed. Overflow pipe does not allow lip overflow at an elevation lower than design Inlet/Outlet Pipe Sediment accumulation Sediment filling 20% or more of the pipe. Inletloutlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet No trash or debris in pipes. pipes (includes floatables and non-floatables). Damaged Cracks wider than'/cinch at the joint of the No cracks more than '/,inch wide at inletioutlet pipes or any evidence of soil entering the joint of the inlet/outlet pipe. at the joints of the inletloutlet pipes. Metal Grates (If Applicable) Unsafe grate opening Grate with opening wider than 7/a inch_ Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% Grate free of trash and debris. of grate surface. footnote to guidelines for disposal Damaged or missing Grate missing or broken members) of the grate. Grate is in place and meets design standards. Manhole Cover/Lid Cover/lid not in place Coverllid is missing or only partially in place_ Coverllid protects opening to Any open structure requires urgent structure. maintenance. Locking mechanism Mechanism cannot be opened by one Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Cover/lid difficult to One maintenance person cannot remove Coverllid can be removed and Remove coverllid after applying 80 lbs. of lift. reinstalled by one maintenance person. 1/9/2009 2009 Surface Water Design Manual — Appendix A A-8 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.5 - CATCH BASINS AND MANHOLES Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed Structure Sediment Sediment exceeds 60% of the depth from the Sump of catch basin contains no bottom of the catch basin to the invert of the sediment. lowest pipe into or out of the catch basin or is within 6 inches of the invert of the lowest pipe into or out of the catch basin. Trash and debris Trash or debris of more than M. cubic foot which No Trash or debris blocking or is located immediately in front of the catch basin potentially blocking entrance to opening or is blocking capacity of the catch basin catch basin. by more than 10%. Trash or debris in the catch basin that exceeds No trash or debris in the catch basin. '/a the depth from the bottom of basin to invert the lowest pipe into or out of the basin. Dead animals or vegetation that could generate No dead animals or vegetation odors that could cause complaints or dangerous present within catch basin. gases (e.g., methane). Deposits of garbage exceeding 1 cubic foot in No condition present which would volume. attract or support the breeding of insects or rodents. Damage to frame Comer of frame extends more than 3/a inch past Frame is even with curb. and/or top slab curb face into the street (If applicable). Top slab has holes larger than 2 square inches or Top slab is free of holes and cracks. cracks wider than % inch. Frame not sitting flush on top slab, i.e., Frame is sitting flush on top slab. separation of more than 3/, inch of the frame from the top slab. Cracks in walls or Cracks wider than % inch and longer than 3 feet, Catch basin is sealed and bottom any evidence of soil particles entering catch structurally sound. basin through cracks, or maintenance person judges that catch basin is unsound. Cracks wider than %: inch and longer than 1 foot No cracks more than '/4 inch wide at at the joint of any inlet/outlet pipe or any evidence the joint of inlet/outlet pipe. of soil particles entering catch basin through cracks. Settlement/ Catch basin has settled more than 1 inch or has Basin replaced or repaired to design misalignment rotated more than 2 inches out of alignment. standards. Damaged pipe joints Cracks wider than '/,inch at the joint of the No cracks more than %-inch wide at inlet/outlet pipes or any evidence of soil entering the joint of inlet/outlet pipes. the catch basin at the joint of the inlet/outlet pipes. Contaminants and Any evidence of contaminants or pollution such Materials removed and disposed of pollution as oil, gasoline, concrete slurries or paint. according to applicable regulations. Source control BMPs implemented if appropriate_ No contaminants present other than a surface oil film. Inlet/Outlet Pipe Sediment Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. accumulation Trash and debris Trash and debris accumulated in inletloutlet No trash or debris in pipes. pipes (includes floatables and non-floatables). Damaged Cracks wider than '/z -inch at the joint of the No cracks more than Y, -inch wide at inletloutlet pipes or any evidence of soil entering the joint of the inlettoutlet pipe, at the joints of the inlet/outlet pipes. 2009 Surface Water Design Manual - Appendix A 1/9/2009 A-9 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.5 - CATCH BASINS AND MANHOLES Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Performed Metal Grates Unsafe grate opening Grate with opening wider than 718 inch. Grate opening meets design (Catch Basins) standards. Trash and debris Trash and debris that is blocking more than 20% Grate free of trash and debris. of grate surface. footnote to guidelines for disposal Damaged or missing Grate missing or broken member(s) of the grate. Grate is in place and meets design Any open structure requires urgent standards. maintenance. Manhole Cover/Lid Cover/lid not in place Coverllid is missing or only partially in place. Cover/lid protects opening to Any open structure requires urgent structure. maintenance. Locking mechanism Mechanism cannot be opened by one Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work_ Cover/lid difficult to One maintenance person cannot remove Cover/lid can be removed and Remove coverllid after applying 80 lbs. of lift. reinstalled by one maintenance person. 1/9/2009 2009 Surface Water Design Manual - Appendix A A-10 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO.6 - CONVEYANCE PIPES AND DITCHES Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed Pipes Sediment & debris Accumulated sediment or debris that exceeds Water flows freely through pipes. accumulation 20% of the diameter of the pipe. Vegetation/roots Vegetationfroots that reduce free movement of Water flows freely through pipes. water through pipes. Contaminants and Any evidence of contaminants or pollution such Materials removed and disposed of pollution as oil, gasoline, concrete slurries or paint. according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damage to protective Protective coating is damaged; rust or corrosion Pipe repaired or replaced. coating or corrosion is weakening the structural integrity of any part of pipe. Damaged Any dent that decreases the cross section area of Pipe repaired or replaced. pipe by more than 20% or is determined to have weakened structural integrity of the pipe. Ditches Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 Trash and debris cleared from square feet of ditch and slopes. ditches. Sediment Accumulated sediment that exceeds 20% of the Ditch cleaned/flushed of all sediment accumulation design depth. and debris so that it matches design. Noxious weeds Any noxious or nuisance vegetation which may Noxious and nuisance vegetation constitute a hazard to County personnel or the removed according to applicable public. regulations. No danger of noxious vegetation where County personnel or the public might normally be. Contaminants and Any evidence of contaminants or pollution such Materials removed and disposed of pollution as oil, gasoline, concrete slurries or paint. according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Vegetation Vegetation that reduces free movement of water Water flows freely through ditches. through ditches. Erosion damage to Any erosion observed on a ditch slope. Slopes are not eroding. slopes Bock lining out of One layer or less of rock exists above native soil Replace rocks to design standards. place or missing (If area 5 square feet or more, any exposed native Applicable) soil. 2009 Surface Water Design Manual - Appendix A 1/9/2009 A- I 1 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE., AND WQ FACILITIES NO. 11 - GROUNDS (LANDSCAPING) Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed Site Trash or litter Any trash and debris which exceed 1 cubic foot Trash and debris cleared from site. per 1,000 square feel (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Noxious weeds Any noxious or nuisance vegetation which may Noxious and nuisance vegetation constitute a hazard to County personnel or the removed according to applicable public. regulations. No danger of noxious vegetation where County personnel or the public might normally be. Contaminants and Any evidence of contaminants or pollution such Materials removed and disposed of pollution as oil, gasoline, concrete slurries or paint. according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Grass/groundcover Grass or groundcover exceeds 18 inches in Grass or groundcover mowed to a height. height no greater than 6 inches. Trees and Shrubs Hazard Any tree or limb of a tree identified as having a No hazard trees in facility. potential to fall and cause property damage or threaten human life. A hazard tree identified by a qualified arborist must be removed as soon as possible. Damaged Limbs or parts of trees or shrubs that are split or Trees and shrubs with less than 5% broken which affect more than 25% of the total of total foliage with split or broken foliage of the tree or shrub. limbs. Trees or shrubs that have been blown down or No blown down vegetation or knocked over. knocked over vegetation. Trees or shrubs free of injury. Trees or shrubs which are not adequately Tree or shrub in place and supported or are leaning over, causing exposure adequately supported; dead or of the roots. diseased trees removed. 1/9/2009 2009 Surface Water Design Manual - Appendix A A-16 CONSTRUCTION PRODUCTS INC. StormFilter Inspection and Maintenance Procedures The Starmwater Management{ StormFilter, Maintenance Guidelines The primary purpose of the Stormwater Management 5tormFilter'8 is to filter out and prevent pollutants from entering our waterways. Like any effective filtration system, periodically these pollutants must be removed to restore the StormFilter to its full efficiency and effectiveness. Maintenance requirements and frequency are dependent on the pollutant load characteristics of each site. Maintenance activities may be required in the event of a chemical spill or due to excessive sediment loading from site erosion or extreme storms. It is a good practice to inspect the system after major storm events. Maintenance Procedures Although there are likely many effective maintenance options, we believe the following procedure is efficient and can be implemented using common equipment and existing maintenance protocols. A two step procedure is recommended as follows: 1, Inspection Inspection of the vault interior to determine the need for maintenance. Z. Maintenance Cartridge replacement Sediment removal Inspection and Maintenance Timing At least one scheduled inspection should take place per year with maintenance following as warranted. First, an inspection should be done before the winter season. During the inspection the need for maintenance should be determined and, if disposal during maintenance will be required, samples of the accumulated sediments and media should be obtained. Second, if warranted, a maintenance (replacement of the filter cartridges and removal of accumulated sediments) should be performed during periods of dry weather. In addition to these two activities, it is important to check the condition of the StormFilter unit after major storms for potential damage caused by high flows and for high sediment accumulation that may be caused by localized erosion in the drainage area. It may be necessary to adjust the inspection/ maintenance schedule depending on the actual operating conditions encountered by the system. In generalr inspection activities can be conducted at any time, and maintenance should occur, if warranted, in late summer to early fall when flows into the system are not likely to be present. Maintenance Frequency The primary factor controlling timing of maintenance of the StormFilter is sediment loading. A properly functioning system will remove solids from water by trapping particulates in the porous structure of the filter media inside the cartridges. The flow through the system will naturally decrease as more and more particulates are trapped. Eventually the flow through the cartridges will be low enough to require replacement. It may be possible to extend the usable span of the cartridges by removing sediment from upstream trapping devices on a routine as -needed basis in order to prevent material from being re -suspended and discharged to the StormFilter treatment system. Site conditions greatly influence maintenance requirements. StormFilter units located in areas with erosion or active construction may need to be inspected and maintained more often than those with fully stabflized surface conditions. The maintenance frequency may be adjusted as additional monitoring information becomes available during the inspection program. Areas that develop known problems should be inspected more frequently than areas that demonstrate no problems, particularly after major storms. Ultimately, inspection and maintenance activities should be scheduled based on the historic records and characteristics of an individual StormFilter system or site. It is recommended that the site owner develop a database to properly manage StormFilter inspection and maintenance programs. Prior to the development of the maintenance database, the following maintenance frequencies should be followed: Inspection One time per year After major storms Maintenance As needed, based on results of inspection (The average maintenance lifecycle is approximately 1-3 years) Per Regulatory requirement In the event of a chemical spill Frequencies should be updated as required. The recommended initial frequency for inspection is one time per year. StormFilter units should be inspected after major storms. 1 t t Sediment removal and cartridge replacement on an as needed basis is recommended unless site conditions warrant. Once an understanding of site characteristics has been established, maintenance may not be needed for one to three years, but inspection is warranted and recommended annually_ inspection Procedures The primary goal of an inspection is to assess the condition of the cartridges relative to the level of visual sediment loading as it relates to decreased treatment capacity. It may be desirable to conduct this inspection during a storm to observe the relative flow through the filter cartridges. If the submerged cartridges are severely plugged, then typically large amounts of sediments will be present and very little flow will be discharged from the drainage pipes. If this is the case, then maintenance is warranted and the cartridges need to be replaced. Warning In the case of a spill, the worker should abort inspection activities until the proper guidance is obtained. Notify the local hazard control agency and CONTECH Construction Products immediately. To conduct an inspection: Important: Inspection should be performed by a person who is familiar with the operation and configuration of the StormFilter treatment unit. 1. If applicable, set up safety equipment to protect and notify surrounding vehicle and pedestrian traffic. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the access portals to the vault and allow the system vent. 4. Without entering the vault, visually inspect the inside of the unit, and note accumulations of liquids and solids. 5. Be sure to record the level of sediment build-up on the floor of the vault, in the forebay, and on top of the cartridges. If fiow is occurring, note the flow of water per drainage pipe. Record all observations. Digital pictures are valuable for historical documentation. 6. Close and fasten the access portals. Y. Remove safety equipment. 8. If appropriate, make notes about the local drainage area relative to ongoing construction, erosion problems, or high loading of other materials to the system. 9. Discuss conditions that suggest maintenance and make decision as to weather or not maintenance is needed. Maintenance Decision Tree The need for maintenance is typically based on results of the inspection. The following Maintenance Decision Tree should be used as a general guide. (Other factors, such as Regulatory Requirements, may need to be considered) 1. Sediment loading on the vault floor. a. If >4" of accumulated sediment, maintenance is required. 2. Sediment loading on top of the cartridge. a. If > 1/4" of accumulation, maintenance is required. 3. Submerged cartridges. a. If >4" of static water in the cartridge bay for more that 24 hours after end of rain event, maintenance is required. 4. Plugged media. a. If pore space between media granules is absent, maintenance is required. 5. Bypass condition. a. If inspection is conducted during an average rain fall event and StormFilter remains in bypass condition (water over the internal outlet baffie wall or submerged cartridges), maintenance is required. 6. Hazardous material release. a. If hazardous material release (automotive fluids or other) is reported, maintenance is required. 7. Pronounced scum line. a. If pronounced scum line (say ? 1/4" thick) is present above top cap, maintenance is required. 8. Calendar Lifecycle. a. If system has not been maintained for 3 years maintenance is required. Assumptions No rainfall for 24 hours or more • No upstream detention (at least not draining into StormFilter) • Structure is online • Outlet pipe is clear of obstruction • Construction bypass is plugged Maintenance Depending on the configuration of the particular system, maintenance personnel will be required to enter the vault to perform the maintenance. Important: If vault entry is required, OSHA rules for confined space entry must be followed. Filter cartridge replacement should occur during dry weather. It may be necessary to plug the filter inlet pipe if base flows is occurring. Replacement cartridges can be delivered to the site or customers facility. Information concerning how to obtain the replacement cartridges is available from CONTECH Construction Products. Warning: In the case of a spill, the maintenance personnel should abort maintenance activities until the proper guidance is obtained. Notify the local hazard control agency and CONTECH Construction Products immediately. To conduct cartridge replacement and sediment removal maintenance: 1. If applicable, set up safety equipment to protect maintenance personnel and pedestrians from site hazards. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the doors (access portals) to the vault and allow the system to vent. 4. Without entering the vault, give the inside of the unit, including components, a general condition inspection. 5. Make notes about the external and internal condition of the vault. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay, and on top of the internal components. 6. Using appropriate equipment offload the replacement cartridges (up to 150 lbs. each) and set aside. 7. Remove used cartridges from the vault using one of the following methods: Method 1: A. This activity will require that maintenance personnel enter the vault to remove the cartridges from the under drain manifold and place them under the vault opening for lifting (removal). Unscrew (counterclockwise rotations) each filter cartridge from the underdrain connector. Roll the loose cartridge, on edge, to a convenient spot beneath the vault access. Using appropriate hoisting equipment, attach a cable from the boom, crane, or tripod to the loose cartridge. Contact CONTECH Construction Products for suggested attachment devices. Important: Note that cartridges containing leaf media (CSF) do not require unscrewing from their connectors. Take care not to damage the manifold connectors. This connector should remain installed in the manifold and could he capped during the maintenance activity to prevent sediments from entering the underdrain manifold. B. Remove the used cartridges (up to 250 lbs. each) from the vault. Important: Care must be used to avoid damaging the cartridges during removal and installation. The cost of repairing components damaged during maintenance will be the responsibility of the owner unless CONTECH Construction Products performs the maintenance activities and damage is not related to discharges to the system. C. Set the used cartridge aside or load onto the hauling truck. D. Continue steps a through c until all cartridges have been removed. Method 2: A. Enter the vault using appropriate confined space protocols. B. Unscrew the cartridge cap. C. Remove the cartridge hood screws (3) hood and float. D. At location under structure access, tip the cartridge on its side. Important: Note that cartridges containing media other than the leaf media require unscrewing from their threaded connectors. Take care not to damage the manifold connectors. This connector should remain installed in the manifold and capped if necessary. D. Empty the cartridge onto the vault floor. Reassemble the empty cartridge. E. Set the empty, used cartridge aside or load onto the hauling truck, F. Continue steps a through e until all cartridges have been removed. 8. Remove accumulated sediment from the floor of the vault and from the forebay. This can most effectively be accomplished by use of a vacuum truck. 9. Once the sediments are removed, assess the condition of the vault and the condition of the connectors. The connectors are short sections of 2 -inch schedule 40 PVC, or threaded schedule 80 PVC that should protrude about 1 " above the floor of the vault. Lightly wash down the vault interior. a. Replace any damaged connectors. 10. Using the vacuum truck boom, crane, or tripod, lower and install the new cartridges. Once again, take care not to damage connections. 11. Close and fasten the door. 12. Remove safety equipment. 13. Finally, dispose of the accumulated materials in accordance with applicable regulations. Make arrangements to return the used empt cartridges to CONTLCH Construction Products. Related Maintenance Activities - Performed on an as -needed basis StormFilter units are often just one of many structures in a more comprehensive stormwater drainage and treatment system. In order for maintenance of the StormFilter to be successful, it is imperative that all other components be properly maintained. The maintenance/repair of upstream facilities should be carried out prior to StormFilter maintenance activities. In addition to considering upstream facilities, it is also important to correct any problems identified in the drainage area. Drainage area concerns may include: erosion problems, heavy oil loading, and discharges of inappropriate materials, Material Disposal The accumulated sediment found in stormwater treatment and conveyance systems must be handled and disposed of in accordance with regulatory protocols. It is possible for sediments to contain measurable concentrations of heavy metals and organic chemicals (such as pesticides and petroleum products). Areas with the greatest potential for high pollutant loading include industrial areas and heavily traveled roads. Sediments and water must be disposed of in accordance with all applicable waste disposal regulations. When scheduling maintenance, consideration must be made for the disposal of solid and liquid wastes. This typically requires coordination with a local landfill for solid waste disposal. For liquid waste disposal a number of options are available including a municipal vacuum truck decant facility, local waste water treatment plant or on-site treatment and discharge. 40 RECvCIED PAPER CON 5TRUCTION PRODUCTS INC. 500.338.1122 www.contech-cpi.com Support • Drawings and specifications are available at contechstormwater.com. • Site-specific design support is available from our engineers. 002009 CONTECH Construction Products Inc. CONTECH Construction Products Inc. provides site solutions for the civil engineering industry. CONTECH's portfolio includes bridges, drainage, sanitary sewer, stormwater and earth stabilization products. For information on other CONTECH division offerings, visit contech-cpi.com or call 800.338.1122 Nothing in this catalog should be construed as an expressed warranty or an implied warranty of merchantability or fitness for any particular purpose. See the CONTECH standard quotation or acknowledgement for applicable warranties and other terms and conditions of sale. The product(s) described may be protected by one or more of thefollowing US patents: 5,322,629; 5,624,575; 5,707,527; 5,759,415; 5,788,848; 5,985,157; 6,027,63% 6,350,374, 6,406,218, 6,641,720; 6,511,595; 6,649,048; 6,991,114; 6,998,038; 7,186,058; related foreign patents or other patents pending. Date: Pe rso n n el: Location: System Size: System Type: Vault ❑ Cast -In -Place ❑ Linear Catch Basin ❑ Manhole ❑ Other ❑ Date: Sediment Thickness in Forebay: Sediment Depth on Vault Floor: Structural Damage: Estimated Flow from Drainage Pipes (if available): Cartridges Submerged- Yes ❑ No ❑ Depth of Standing Water: Storm Filter Maintenance Activities (check off if done and give description) ❑ Trash and Debris Removal: F-1 Minor Structural Renairs: ❑ Drainage Area Report Excessive Oil Loading: Yes [] No ❑ Source: Sediment Accumulation on Pavement: Yes ❑ No ❑ Source: Erosion of Landscaped Areas: Yes ❑ No ❑ Source: Items Needing Further Work: Owners should contact the local public works department and inquire about how the department disposes of their street waste residuals. Other Comments: Review the condition reports from the previous inspection visits. Date: Personnel: Location: System Size: System Type: Vault ❑ Cast -In -Place ❑ Linear Catch Basin ❑ Manhole ❑ Other ❑ List Safety Procedures and Equipment Used: System Observations Months in Service: Oil in Forebay: Yes ❑ No ❑ Sediment Depth in Forebay: ❑ Details: Sediment Depth on Vault Floor: Yes ❑ Structural Damage: ❑ Details: Sediment Removed: Yes ❑ Drainage Area Report ❑ Details: Excessive Oil Loading: Yes ❑ No ❑ Source: Sediment Accumulation on Pavement: Yes [] No ❑ Source: Erosion of Landscaped Areas: Yes ❑ No ❑ Source: StormFilter Cartridge Replacement Maintenance Activities Remove Trash and Debris: Yes ❑ No ❑ Details: Replace Cartridges: Yes ❑ No ❑ Details: Sediment Removed: Yes ❑ No ❑ Details: Quantity of Sediment Removed (estimate?): Minor Structural Repairs: Yes ❑ No ❑ Details: Residuals (debris, sediment) Disposal Methods: Notes: Save Valuable Land and Protect Water Resources ~ - r StormlTeche Detention • Retention • Recharge Subsurface Stormwater Management"' R .4 IsolatorTM Row 0&M Manual StormTech' Chamber System for Stormwater Management 1,0 The Isolator7M Row 1.1 INTRODUCTION An important component of any Stormwater Pollution Prevention Plan Is inspection and maintenance. The StormTech Isolator Row is a patent pending technique to inexpensively enhance Total Suspended Solids (TSS) removal and provide easy access for inspection and maintenance. Looking down the Isolator Row from the manhole opening, woven geotextile is shown between the chamber and stone base. 1.2 THE ISOLATOR' ROW The Isolator Row is a row of StormTech chambers, either SC -310, SC -740 or MC -3500 models, that is surrounded with filter fabric and connected to a closely located man- hole for easy access. The fabric -wrapped chambers provide for settling and filtration of sediment as storm water rises in the Isolator Row and ultimately passes through the filter fabric. The open bottom chambers and perforated sidewalls allow storm water to flow both verti- cally and horizontally out of the chambers. Sediments are captured in the Isolator Row protecting the storage areas of the adjacent stone and chambers from sedi- ment accumulation. Two different fabrics are used for the Isolator Row. A woven geotextile fabric is placed between the stone and the Isolator Row chambers. The tough geotextile provides a media for storm water filtration and provides a durable surface for maintenance operations. It is also designed to prevent scour of the underlying stone and remain intact during high pressure jetting. A non -woven fabric is placed over the chambers to provide a filter media for flows passing through the perforations In the sidewall of the chamber. The Isolator Row is typically designed to capture the "first flush" and offers the versatility to be sized on a vol- ume basis or flow rate basis. An upstream manhole not only provides access to the Isolator Row but typically includes a high flow weir such that storm water flowrates or volumes that exceed the capacity of the Isolator Row overtop the over flow weir and discharge through a manifold to the other chambers. The Isolator Row may also be part of a treatment train. By treating storm water prior to entry into the chamber system, the service life can be extended and pollutants such as hydrocarbons can be captured. Pre-treatment best management practices can be as simple as deep sump catch basins, oil -water separators or can be inno- vative storm water treatment devices. The design of the treatment train and selection of pretreatment devices by the design engineer s often driven by regulatory requirements. Whether pretreatment is used or not, the Isolator Row is recommended by StormTech as an effective means to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row. StormTech Isolator Row with Overflow Spillway (not to scale) MANHOLE WITH OVERFLOW WEIR ECCENTRIC OPTIONAL ACCESS Call Storm Tech at 888.892.2694 cr visit cur websile at www.stormtech.corn for technical and product information. 2.0 Isolator Row Inspection/Maintenance 2.1 INSPECTION The frequency of Inspection and Maintenance varies by location. A routine inspection schedule needs to be established for each individual iocatior based upon site specific variables. The type of land use (i.e, industrial, commerciai residential), anticipated pollutant load, per- cent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspec- tions. Initially, the Isolator Row should be inspected every 6 months for the first year of operation. For subsequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row incorporates a combination of standarc manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be Inserted to deter- mine tre depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row, clean-cut should be performed. 2.2 MAINTENANCE The Isolator Raw was designed to reduce the cost of periodic maintenance. By "isolating" sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for main- tenance, access is provided via a manholes) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. StormTech Isolator Row (not to scale) CATCH BASIN OR MANHOLE 114 StormTech° Examples of culvert cleaning nozzles appropriate for Isolator Row maintenance. (These are not StormTech products.) Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water noz- zle to propel itself down the Isolator Row while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are Flushed back into the man- hole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for cul- verts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45" are best. Most JetVac reels have 440 feet of hose allow- ing maintenance of an Isolator Row up to 50 chambers long. The JetVac process shall only be performed on StormTech Isolator Rows that have AASHTO class 1 woven geotextile (as specified by StormTech) over their angular base stone. INSPECTION PORT LOCATION PER ENGINEER'S DRAWING COVER ENTIRE ROW WITH AASHTO M289 CLASS 2 NON -WOVEN GEOTEXTILE "" 0 - 5'(1.5 m) WIDE STRIP SC -740 - 8'(2.4 m) WIDE STRIP r STORMTECH ��MC�3500 - 12,5'(3.8 m) WIDE STRIP I END CAP a SllNP f]FP'TH --� -�I / HV ESI �R ENGPEER SC -310 - 12" (300 mm} PIPE 2 LAYERS OF WOVEN GEOTEXTILE THAT MEETS AASHTO M288 CLASS 1 SO -740 - 24' (600 mm) PIPE REQUIREMENTS, 86TVVEEN STONE BASE AND CHAMBERS MC -3500-24" (600 mm) PIPE SC -310.4'(1.2 m} WIDE STRIP SC -740 - 5'-6'(1.5 m) WiOE STRIP MC -3500 - 15 m) WIDE STRIP Call Storm €ech at 868.892.2694 or visit our website at www.stormtech.com for technical and product information 3 t. '�Af�rt��IIrrlIAIAIAIf`�IAIA1#IA 11IlAll11111111�milki�lA 1I�rff 11 a SllNP f]FP'TH --� -�I / HV ESI �R ENGPEER SC -310 - 12" (300 mm} PIPE 2 LAYERS OF WOVEN GEOTEXTILE THAT MEETS AASHTO M288 CLASS 1 SO -740 - 24' (600 mm) PIPE REQUIREMENTS, 86TVVEEN STONE BASE AND CHAMBERS MC -3500-24" (600 mm) PIPE SC -310.4'(1.2 m} WIDE STRIP SC -740 - 5'-6'(1.5 m) WiOE STRIP MC -3500 - 15 m) WIDE STRIP Call Storm €ech at 868.892.2694 or visit our website at www.stormtech.com for technical and product information 3 3.0 Isolator Row Step By Step Maintenance Procedures Step 1) Inspect Isolator Row for sediment StormTech Isolator Row (not to scale) A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser di. Using a flashlight and stadia rod, measure depth of sediment and record results on maintenance log. iv. If sediment is at, or above, 3 inch depth proceed to Step 2. If not proceed to step 3. B) All Isolator Rows i, Remove cover from manhole at upstream end of Isolator Row ii. Using a flashiight, inspect down Isolator Row through outlet pipe 1. Mirrors on poles or cameras may be used to avoid a confined space entry 2. Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches) proceed to Step 2 If not proceed to Step 3. Step 2) Glean out Isolator Row using the JetVac process A) A fixed culvert cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3) Replace all caps, lids and covers, record observations and actions Slap 4) Inspect & clean catch basins and manholes upstream of the StormTech system Sample Maintenance Log S1orm1T;e9ch8 Detention • Retention • Recharge Subsurface Stormwater Management"' 29 Beaver Road, Suite 104 i Wethersfield I Connecticut 106109 860.529.8188 f 888.892.2694 fax 866.328.8401 1 www.stormtech.corn StormTech products are covered by one or more of 1he following patents: U.S. Patents: 5,401,459; 5,511,903; 5,716,163; 5,588,778-15,839,844: Canadian Patents: 2,158,418 Other U.S. and Foreign Patents Pending Printed in U.S.A. a Copyright. All rights reserved. StormTech LLC, 2009 5090809 Stadia Rod Readings11 0I!Fixed I. Fixed point Sediment Depth Observations/Actions Inspector 1 !' 1 11 1 bottom sediment 3/15/01 6.3 ft. none New in5tal:ation. Fixed oint 15 0 frame at grade djm 912410" 6.2 0.1 ft. Qome grit felt 5m 6120103 5.8 0.5 ft. Mucky feel, debris visible in manhole and in ry l5olator row, maintenance due 7/7103 6.3 ft. 0 5yatem.etted and vacuumed djm S1orm1T;e9ch8 Detention • Retention • Recharge Subsurface Stormwater Management"' 29 Beaver Road, Suite 104 i Wethersfield I Connecticut 106109 860.529.8188 f 888.892.2694 fax 866.328.8401 1 www.stormtech.corn StormTech products are covered by one or more of 1he following patents: U.S. Patents: 5,401,459; 5,511,903; 5,716,163; 5,588,778-15,839,844: Canadian Patents: 2,158,418 Other U.S. and Foreign Patents Pending Printed in U.S.A. a Copyright. All rights reserved. StormTech LLC, 2009 5090809